1 # tzdb data for North and Central America and environs
3 # This file is in the public domain, so clarified as of
4 # 2009-05-17 by Arthur David Olson.
6 # also includes Central America and the Caribbean
8 # This file is by no means authoritative; if you think you know better,
9 # go ahead and edit the file (and please send any changes to
10 # tz@iana.org for general use in the future). For more, please see
11 # the file CONTRIBUTING in the tz distribution.
13 # From Paul Eggert (1999-03-22):
14 # A reliable and entertaining source about time zones is
15 # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997).
17 ###############################################################################
21 # From Paul Eggert (1999-03-31):
22 # Howse writes (pp 121-125) that time zones were invented by
23 # Professor Charles Ferdinand Dowd (1825-1904),
24 # Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY).
25 # His pamphlet "A System of National Time for Railroads" (1870)
26 # was the result of his proposals at the Convention of Railroad Trunk Lines
27 # in New York City (1869-10). His 1870 proposal was based on Washington, DC,
28 # but in 1872-05 he moved the proposed origin to Greenwich.
30 # From Paul Eggert (2018-03-20):
31 # Dowd's proposal left many details unresolved, such as where to draw
32 # lines between time zones. The key individual who made time zones
33 # work in the US was William Frederick Allen - railway engineer,
34 # managing editor of the Travelers' Guide, and secretary of the
35 # General Time Convention, a railway standardization group. Allen
36 # spent months in dialogs with scientific and railway leaders,
37 # developed a workable plan to institute time zones, and presented it
38 # to the General Time Convention on 1883-04-11, saying that his plan
39 # meant "local time would be practically abolished" - a plus for
40 # railway scheduling. By the next convention on 1883-10-11 nearly all
41 # railroads had agreed and it took effect on 1883-11-18. That Sunday
42 # was called the "day of two noons", as some locations observed noon
43 # twice. Allen witnessed the transition in New York City, writing:
45 # I heard the bells of St. Paul's strike on the old time. Four
46 # minutes later, obedient to the electrical signal from the Naval
47 # Observatory ... the time-ball made its rapid descent, the chimes
48 # of old Trinity rang twelve measured strokes, and local time was
49 # abandoned, probably forever.
51 # Most of the US soon followed suit. See:
52 # Bartky IR. The adoption of standard time. Technol Cult 1989 Jan;30(1):25-56.
53 # https://dx.doi.org/10.2307/3105430
55 # From Paul Eggert (2005-04-16):
56 # That 1883 transition occurred at 12:00 new time, not at 12:00 old time.
57 # See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005).
59 # From Paul Eggert (2006-03-22):
60 # A good source for time zone historical data in the US is
61 # Thomas G. Shanks, The American Atlas (5th edition),
62 # San Diego: ACS Publications, Inc. (1991).
63 # Make sure you have the errata sheet; the book is somewhat useless without it.
64 # It is the source for most of the pre-1991 US entries below.
66 # From Paul Eggert (2001-03-06):
67 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
68 # in his whimsical essay "An Economical Project for Diminishing the Cost
69 # of Light" published in the Journal de Paris (1784-04-26).
70 # Not everyone is happy with the results:
72 # I don't really care how time is reckoned so long as there is some
73 # agreement about it, but I object to being told that I am saving
74 # daylight when my reason tells me that I am doing nothing of the kind.
75 # I even object to the implication that I am wasting something
76 # valuable if I stay in bed after the sun has risen. As an admirer
77 # of moonlight I resent the bossy insistence of those who want to
78 # reduce my time for enjoying it. At the back of the Daylight Saving
79 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
80 # to push people into bed earlier, and get them up earlier, to make
81 # them healthy, wealthy and wise in spite of themselves.
83 # -- Robertson Davies, The diary of Samuel Marchbanks,
84 # Clarke, Irwin (1947), XIX, Sunday
86 # For more about the first ten years of DST in the United States, see
87 # Robert Garland, Ten years of daylight saving from the Pittsburgh standpoint
88 # (Carnegie Library of Pittsburgh, 1927).
89 # https://web.archive.org/web/20160517155308/http://www.clpgh.org/exhibit/dst.html
91 # Shanks says that DST was called "War Time" in the US in 1918 and 1919.
92 # However, DST was imposed by the Standard Time Act of 1918, which
93 # was the first nationwide legal time standard, and apparently
94 # time was just called "Standard Time" or "Daylight Saving Time".
96 # From Paul Eggert (2019-06-04):
97 # Here is the legal basis for the US federal rules.
98 # * Public Law 65-106 (1918-03-19) implemented standard and daylight saving
99 # time for the first time across the US, springing forward on March's last
100 # Sunday and falling back on October's last Sunday.
101 # https://www.loc.gov/law/help/statutes-at-large/65th-congress/session-2/c65s2ch24.pdf
102 # * Public Law 66-40 (1919-08-20) repealed DST on October 1919's last Sunday.
103 # https://www.loc.gov/law/help/statutes-at-large/66th-congress/session-1/c66s1ch51.pdf
104 # * Public Law 77-403 (1942-01-20) started wartime DST on 1942-02-09.
105 # https://www.loc.gov/law/help/statutes-at-large/77th-congress/session-2/c77s2ch7.pdf
106 # * Public Law 79-187 (1945-09-25) ended wartime DST on 1945-09-30.
107 # https://www.loc.gov/law/help/statutes-at-large/79th-congress/session-1/c79s1ch388.pdf
108 # * Public Law 89-387 (1966-04-13) reinstituted a national standard for DST,
109 # from April's last Sunday to October's last Sunday, effective 1967.
110 # https://www.govinfo.gov/content/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf
111 # * Public Law 93-182 (1973-12-15) moved the 1974 spring-forward to 01-06.
112 # https://www.govinfo.gov/content/pkg/STATUTE-87/pdf/STATUTE-87-Pg707.pdf
113 # * Public Law 93-434 (1974-10-05) moved the 1975 spring-forward to
114 # February's last Sunday.
115 # https://www.govinfo.gov/content/pkg/STATUTE-88/pdf/STATUTE-88-Pg1209.pdf
116 # * Public Law 99-359 (1986-07-08) moved the spring-forward to April's first
118 # https://www.govinfo.gov/content/pkg/STATUTE-100/pdf/STATUTE-100-Pg764.pdf
119 # * Public Law 109-58 (2005-08-08), effective 2007, moved the spring-forward
120 # to March's second Sunday and the fall-back to November's first Sunday.
121 # https://www.govinfo.gov/content/pkg/PLAW-109publ58/pdf/PLAW-109publ58.pdf
122 # All transitions are at 02:00 local time.
124 # From Arthur David Olson:
125 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
126 # Daylight Saving Time in the US was by local option, except during wartime.
128 # From Arthur David Olson (2000-09-25):
129 # Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama.
130 # In the introduction, Oboler spoke of "Eastern Peace Time."
131 # An AltaVista search turned up:
132 # https://web.archive.org/web/20000926032210/http://rowayton.org/rhs/hstaug45.html
133 # "When the time is announced over the radio now, it is 'Eastern Peace
134 # Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful."
135 # (August 1945) by way of confirmation.
137 # From Paul Eggert (2017-09-23):
138 # This was the V-J Day issue of the Clamdigger, a Rowayton, CT newsletter.
140 # From Joseph Gallant citing
141 # George H. Douglas, _The Early Days of Radio Broadcasting_ (1987):
142 # At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set
143 # to switch to London for Attlee's address, but the American people
144 # never got to hear his speech live. According to one press account,
145 # CBS' Bob Trout was first to announce the word of Japan's surrender,
146 # but a few seconds later, NBC, ABC and Mutual also flashed the word
147 # of surrender, all of whom interrupting the bells of Big Ben in
148 # London which were to precede Mr. Attlee's speech.
150 # From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From
151 # Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times:
153 # ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender.
154 # Any announcement from Asia would reach St. John's New York newsroom on a
155 # wire service teletype machine, which had prescribed signals for major news.
156 # Associated Press, for example, would ring five bells before spewing out
157 # typed copy of an important story, and 10 bells for news "of transcendental
160 # On Aug. 14, stalling while talking steadily into the NBC networks' open
161 # microphone, St. John heard five bells and waited only to hear a sixth bell,
162 # before announcing confidently: "Ladies and gentlemen, World War II is over.
163 # The Japanese have agreed to our surrender terms."
165 # He had scored a 20-second scoop on other broadcasters.
167 # From Arthur David Olson (2005-08-22):
168 # Paul has been careful to use the "US" rules only in those locations
169 # that are part of the United States; this reflects the real scope of
170 # U.S. government action. So even though the "US" rules have changed
171 # in the latest release, other countries won't be affected.
173 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
174 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
175 Rule US 1918 1919 - Oct lastSun 2:00 0 S
176 Rule US 1942 only - Feb 9 2:00 1:00 W # War
177 Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace
178 Rule US 1945 only - Sep 30 2:00 0 S
179 Rule US 1967 2006 - Oct lastSun 2:00 0 S
180 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
181 Rule US 1974 only - Jan 6 2:00 1:00 D
182 Rule US 1975 only - Feb lastSun 2:00 1:00 D
183 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
184 Rule US 1987 2006 - Apr Sun>=1 2:00 1:00 D
185 Rule US 2007 max - Mar Sun>=8 2:00 1:00 D
186 Rule US 2007 max - Nov Sun>=1 2:00 0 S
188 # From Arthur David Olson, 2005-12-19
189 # We generate the files specified below to guard against old files with
190 # obsolete information being left in the time zone binary directory.
191 # We limit the list to names that have appeared in previous versions of
192 # this time zone package.
193 # We do these as separate Zones rather than as Links to avoid problems if
194 # a particular place changes whether it observes DST.
195 # We put these specifications here in the northamerica file both to
196 # increase the chances that they'll actually get compiled and to
197 # avoid the need to duplicate the US rules in another file.
199 # Zone NAME STDOFF RULES FORMAT [UNTIL]
202 Zone HST -10:00 - HST
203 Zone EST5EDT -5:00 US E%sT
204 Zone CST6CDT -6:00 US C%sT
205 Zone MST7MDT -7:00 US M%sT
206 Zone PST8PDT -8:00 US P%sT
208 # From U. S. Naval Observatory (1989-01-19):
209 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
210 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
211 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
212 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
213 # USA MOUNTAIN 7 H BEHIND UTC DENVER
214 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
215 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
216 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
217 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
218 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
219 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
220 # USA " 9 H BEHIND UTC APR 3 - OCT 30
221 # USA HAWAII 10 H BEHIND UTC
222 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
224 # From Arthur David Olson (1989-01-21):
225 # The above dates are for 1988.
226 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
227 # no DST in Samoa, and the claim that there is DST in Alaska and the
230 # From Arthur David Olson (1988-02-13):
231 # Legal standard time zone names, from United States Code (1982 Edition and
232 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
233 # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966
234 # took effect), as explained in sections 263 and 261:
236 # United States standard eastern time
237 # United States standard mountain time
238 # United States standard central time
239 # United States standard Pacific time
241 # United States standard Alaska time
243 # Next, names from 1967-04-01 until 1983-11-30 (the date for
244 # public law 98-181):
245 # Atlantic standard time
246 # eastern standard time
247 # central standard time
248 # mountain standard time
249 # Pacific standard time
250 # Yukon standard time
251 # Alaska-Hawaii standard time
252 # Bering standard time
253 # And after 1983-11-30:
254 # Atlantic standard time
255 # eastern standard time
256 # central standard time
257 # mountain standard time
258 # Pacific standard time
259 # Alaska standard time
260 # Hawaii-Aleutian standard time
261 # Samoa standard time
262 # The law doesn't give abbreviations.
264 # From Paul Eggert (2016-12-19):
265 # Here are URLs for the 1918 and 1966 legislation:
266 # http://uscode.house.gov/statviewer.htm?volume=40&page=451
267 # http://uscode.house.gov/statviewer.htm?volume=80&page=108
268 # Although the 1918 names were officially "United States Standard
269 # Eastern Time" and similarly for "Central", "Mountain", "Pacific",
270 # and "Alaska", in practice "Standard" was placed just before "Time",
271 # as codified in 1966. In practice, Alaska time was abbreviated "AST"
272 # before 1968. Summarizing the 1967 name changes:
273 # 1918 names 1967 names
274 # -08 Standard Pacific Time (PST) Pacific standard time (PST)
275 # -09 (unofficial) Yukon (YST) Yukon standard time (YST)
276 # -10 Standard Alaska Time (AST) Alaska-Hawaii standard time (AHST)
277 # -11 (unofficial) Nome (NST) Bering standard time (BST)
279 # From Paul Eggert (2000-01-08), following a heads-up from Rives McDow:
280 # Public law 106-564 (2000-12-23) introduced ... "Chamorro Standard Time"
281 # for time in Guam and the Northern Marianas. See the file "australasia".
283 # From Paul Eggert (2015-04-17):
284 # HST and HDT are standardized abbreviations for Hawaii-Aleutian
285 # standard and daylight times. See section 9.47 (p 234) of the
286 # U.S. Government Printing Office Style Manual (2008)
287 # https://www.gpo.gov/fdsys/pkg/GPO-STYLEMANUAL-2008/pdf/GPO-STYLEMANUAL-2008.pdf
289 # From Arthur David Olson, 2005-08-09
290 # The following was signed into law on 2005-08-08.
292 # H.R. 6, Energy Policy Act of 2005, SEC. 110. DAYLIGHT SAVINGS.
293 # (a) Amendment.--Section 3(a) of the Uniform Time Act of 1966 (15
294 # U.S.C. 260a(a)) is amended--
295 # (1) by striking "first Sunday of April" and inserting "second
296 # Sunday of March"; and
297 # (2) by striking "last Sunday of October" and inserting "first
298 # Sunday of November'.
299 # (b) Effective Date.--Subsection (a) shall take effect 1 year after the
300 # date of enactment of this Act or March 1, 2007, whichever is later.
301 # (c) Report to Congress.--Not later than 9 months after the effective
302 # date stated in subsection (b), the Secretary shall report to Congress
303 # on the impact of this section on energy consumption in the United
305 # (d) Right to Revert.--Congress retains the right to revert the
306 # Daylight Saving Time back to the 2005 time schedules once the
307 # Department study is complete.
309 # US eastern time, represented by New York
311 # Connecticut, Delaware, District of Columbia, most of Florida,
312 # Georgia, southeast Indiana (Dearborn and Ohio counties), eastern Kentucky
313 # (except America/Kentucky/Louisville below), Maine, Maryland, Massachusetts,
314 # New Hampshire, New Jersey, New York, North Carolina, Ohio,
315 # Pennsylvania, Rhode Island, South Carolina, eastern Tennessee,
316 # Vermont, Virginia, West Virginia
318 # From Dave Cantor (2004-11-02):
319 # Early this summer I had the occasion to visit the Mount Washington
320 # Observatory weather station atop (of course!) Mount Washington [, NH]....
321 # One of the staff members said that the station was on Eastern Standard Time
322 # and didn't change their clocks for Daylight Saving ... so that their
323 # reports will always have times which are 5 hours behind UTC.
325 # From Paul Eggert (2005-08-26):
326 # According to today's Huntsville Times
327 # http://www.al.com/news/huntsvilletimes/index.ssf?/base/news/1125047783228320.xml&coll=1
328 # a few towns on Alabama's "eastern border with Georgia, such as Phenix City
329 # in Russell County, Lanett in Chambers County and some towns in Lee County,
330 # set their watches and clocks on Eastern time." It quotes H.H. "Bubba"
331 # Roberts, city administrator in Phenix City. as saying "We are in the Central
332 # time zone, but we do go by the Eastern time zone because so many people work
335 # From Paul Eggert (2017-02-22):
336 # Four cities are involved. The two not mentioned above are Smiths Station
337 # and Valley. Barbara Brooks, Valley's assistant treasurer, heard it started
338 # because West Point Pepperell textile mills were in Alabama while the
339 # corporate office was in Georgia, and residents voted to keep Eastern
340 # time even after the mills closed. See: Kazek K. Did you know which
341 # Alabama towns are in a different time zone? al.com 2017-02-06.
342 # http://www.al.com/living/index.ssf/2017/02/do_you_know_which_alabama_town.html
344 # From Paul Eggert (2014-09-06):
345 # Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208
346 # says that New York City Hall time was 3 minutes 58.4 seconds fast of
347 # Eastern time (i.e., -4:56:01.6) just before the 1883 switch.
349 # Rule NAME FROM TO - IN ON AT SAVE LETTER
350 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
351 Rule NYC 1920 only - Oct lastSun 2:00 0 S
352 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
353 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
354 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
355 # Zone NAME STDOFF RULES FORMAT [UNTIL]
357 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 17:00u
364 # US central time, represented by Chicago
366 # Alabama, Arkansas, Florida panhandle (Bay, Calhoun, Escambia,
367 # Gulf, Holmes, Jackson, Okaloosa, Santa Rosa, Walton, and
368 # Washington counties), Illinois, western Indiana
369 # (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
370 # Vanderburgh, and Warrick counties), Iowa, most of Kansas, western
371 # Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern
372 # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota,
373 # western Tennessee, most of Texas, Wisconsin
375 # From Paul Eggert (2018-01-07):
376 # In 1869 the Chicago Astronomical Society contracted with the city to keep
377 # time. Though delayed by the Great Fire, by 1880 a wire ran from the
378 # Dearborn Observatory (on the University of Chicago campus) to City Hall,
379 # which then sent signals to police and fire stations. However, railroads got
380 # their time signals from the Allegheny Observatory, the Madison Observatory,
381 # the Ann Arbor Observatory, etc., so their clocks did not agree with each
382 # other or with the city's official time. The confusion took some years to
384 # Moser M. How Chicago gave America its time zones. Chicago. 2018-01-04.
385 # http://www.chicagomag.com/city-life/January-2018/How-Chicago-Gave-America-Its-Time-Zones/
387 # From Larry M. Smith (2006-04-26) re Wisconsin:
388 # https://docs.legis.wisconsin.gov/statutes/statutes/175.pdf
389 # is currently enforced at the 01:00 time of change. Because the local
390 # "bar time" in the state corresponds to 02:00, a number of citations
391 # are issued for the "sale of class 'B' alcohol after prohibited
392 # hours" within the deviated hour of this change every year....
394 # From Douglas R. Bomberg (2007-03-12):
395 # Wisconsin has enacted (nearly eleventh-hour) legislation to get WI
396 # Statue 175 closer in synch with the US Congress' intent....
397 # https://docs.legis.wisconsin.gov/2007/related/acts/3
399 # From an email administrator of the City of Fort Pierre, SD (2015-12-21):
400 # Fort Pierre is technically located in the Mountain time zone as is
401 # the rest of Stanley County. Most of Stanley County and Fort Pierre
402 # uses the Central time zone due to doing most of their business in
403 # Pierre so it simplifies schedules. I have lived in Stanley County
404 # all my life and it has been that way since I can remember. (43 years!)
406 # From Paul Eggert (2015-12-25):
407 # Assume this practice predates 1970, so Fort Pierre can use America/Chicago.
409 # From Paul Eggert (2015-04-06):
410 # In 1950s Nashville a public clock had dueling faces, one for conservatives
411 # and the other for liberals; the two sides didn't agree about the time of day.
412 # I haven't found a photo of this clock, nor have I tracked down the TIME
413 # magazine report cited below, but here's the story as told by the late
414 # American journalist John Seigenthaler, who was there:
416 # "The two [newspaper] owners held strongly contrasting political and
417 # ideological views. Evans was a New South liberal, Stahlman an Old South
418 # conservative, and their two papers frequently clashed editorially, often on
419 # the same day.... In the 1950s as the state legislature was grappling with
420 # the question of whether to approve daylight saving time for the entire state,
421 # TIME magazine reported:
423 # "'The Nashville Banner and The Nashville Tennessean rarely agree on anything
424 # but the time of day - and last week they couldn't agree on that.'
426 # "It was all too true. The clock on the front of the building had two faces -
427 # The Tennessean side of the building facing west, the other, east. When it
428 # was high noon Banner time, it was 11 a.m. Tennessean time."
430 # Seigenthaler J. For 100 years, Tennessean had it covered.
431 # The Tennessean 2007-05-11, republished 2015-04-06.
432 # https://www.tennessean.com/story/insider/extras/2015/04/06/archives-seigenthaler-for-100-years-the-tennessean-had-it-covered/25348545/
434 # Rule NAME FROM TO - IN ON AT SAVE LETTER
435 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
436 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
437 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
438 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
439 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
440 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
441 # Zone NAME STDOFF RULES FORMAT [UNTIL]
442 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 18:00u
444 -6:00 Chicago C%sT 1936 Mar 1 2:00
445 -5:00 - EST 1936 Nov 15 2:00
446 -6:00 Chicago C%sT 1942
448 -6:00 Chicago C%sT 1967
450 # Oliver County, ND switched from mountain to central time on 1992-10-25.
451 Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 19:00u
452 -7:00 US M%sT 1992 Oct 25 2:00
454 # Morton County, ND, switched from mountain to central time on
455 # 2003-10-26, except for the area around Mandan which was already central time.
456 # See <http://dmses.dot.gov/docimages/p63/135818.pdf>.
457 # Officially this switch also included part of Sioux County, and
458 # Jones, Mellette, and Todd Counties in South Dakota;
459 # but in practice these other counties were already observing central time.
460 # See <http://www.epa.gov/fedrgstr/EPA-IMPACT/2003/October/Day-28/i27056.htm>.
461 Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 19:00u
462 -7:00 US M%sT 2003 Oct 26 2:00
465 # From Josh Findley (2011-01-21):
466 # ...it appears that Mercer County, North Dakota, changed from the
467 # mountain time zone to the central time zone at the last transition from
468 # daylight-saving to standard time (on Nov. 7, 2010):
469 # https://www.gpo.gov/fdsys/pkg/FR-2010-09-29/html/2010-24376.htm
470 # http://www.bismarcktribune.com/news/local/article_1eb1b588-c758-11df-b472-001cc4c03286.html
472 # From Andy Lipscomb (2011-01-24):
473 # ...according to the Census Bureau, the largest city is Beulah (although
474 # it's commonly referred to as Beulah-Hazen, with Hazen being the next
475 # largest city in Mercer County). Google Maps places Beulah's city hall
476 # at 47° 15' 51" N, 101° 46' 40" W, which yields an offset of 6h47'07".
478 Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 19:00u
479 -7:00 US M%sT 2010 Nov 7 2:00
482 # US mountain time, represented by Denver
484 # Colorado, far western Kansas, Montana, western
485 # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City),
486 # New Mexico, southwestern North Dakota,
487 # western South Dakota, far western Texas (El Paso County, Hudspeth County,
488 # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming
490 # From Paul Eggert (2018-10-25):
491 # On 1921-03-04 federal law placed all of Texas into the central time zone.
492 # However, El Paso ignored the law for decades and continued to observe
493 # mountain time, on the grounds that that's what they had always done
494 # and they weren't about to let the federal government tell them what to do.
495 # Eventually the federal government gave in and changed the law on
496 # 1970-04-10 to match what El Paso was actually doing. Although
497 # that's slightly after our 1970 cutoff, there is no need to create a
498 # separate zone for El Paso since they were ignoring the law anyway. See:
499 # Long T. El Pasoans were time rebels, fought to stay in Mountain zone.
500 # El Paso Times. 2018-10-24 06:40 -06.
501 # https://www.elpasotimes.com/story/news/local/el-paso/2018/10/24/el-pasoans-were-time-rebels-fought-stay-mountain-zone/1744509002/
503 # Rule NAME FROM TO - IN ON AT SAVE LETTER
504 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
505 Rule Denver 1920 only - Oct lastSun 2:00 0 S
506 Rule Denver 1921 only - May 22 2:00 0 S
507 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
508 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
509 # Zone NAME STDOFF RULES FORMAT [UNTIL]
510 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 19:00u
512 -7:00 Denver M%sT 1942
514 -7:00 Denver M%sT 1967
517 # US Pacific time, represented by Los Angeles
519 # California, northern Idaho (Benewah, Bonner, Boundary, Clearwater,
520 # Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties, Idaho county
521 # north of the Salmon River, and the towns of Burgdorf and Warren),
522 # Nevada (except West Wendover), Oregon (except the northern ¾ of
523 # Malheur county), and Washington
525 # From Paul Eggert (2016-08-20):
526 # In early February 1948, in response to California's electricity shortage,
527 # PG&E changed power frequency from 60 to 59.5 Hz during daylight hours,
528 # causing electric clocks to lose six minutes per day. (This did not change
529 # legal time, and is not part of the data here.) See:
530 # Ross SA. An energy crisis from the past: Northern California in 1948.
531 # Working Paper No. 8, Institute of Governmental Studies, UC Berkeley,
532 # 1973-11. https://escholarship.org/uc/item/8x22k30c
534 # In another measure to save electricity, DST was instituted from 1948-03-14
535 # at 02:01 to 1949-01-16 at 02:00, with the governor having the option to move
536 # the fallback transition earlier. See pages 3-4 of:
537 # http://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1948/48Vol1_Chapters.pdf
541 # Governor Warren received a torrent of objecting mail, and it is not too much
542 # to speculate that the objections to Daylight Saving Time were one important
543 # factor in the defeat of the Dewey-Warren Presidential ticket in California.
546 # On December 8 the governor exercised the option, setting the date to January 1
547 # (LA Times 1948-12-09). The transition time was 02:00 (LA Times 1949-01-01).
549 # Despite the controversy, in 1949 California voters approved Proposition 12,
550 # which established DST from April's last Sunday at 01:00 until September's
551 # last Sunday at 02:00. This was amended by 1962's Proposition 6, which changed
552 # the fall-back date to October's last Sunday. See:
553 # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1501&context=ca_ballot_props
554 # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1636&context=ca_ballot_props
556 # Rule NAME FROM TO - IN ON AT SAVE LETTER
557 Rule CA 1948 only - Mar 14 2:01 1:00 D
558 Rule CA 1949 only - Jan 1 2:00 0 S
559 Rule CA 1950 1966 - Apr lastSun 1:00 1:00 D
560 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
561 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
562 # Zone NAME STDOFF RULES FORMAT [UNTIL]
563 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 20:00u
569 # AK%sT is the modern abbreviation for -09 per USNO.
571 # From Paul Eggert (2017-06-15):
572 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
573 # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia.
574 # On Friday, 1867-10-18 (Gregorian), at precisely 15:30 local time, the
575 # Russian forts and fleet at Sitka fired salutes to mark the ceremony of
576 # formal transfer. See the Sacramento Daily Union (1867-11-14), p 3, col 2.
577 # https://cdnc.ucr.edu/cgi-bin/cdnc?a=d&d=SDU18671114.2.12.1
578 # Sitka workers did not change their calendars until Sunday, 1867-10-20,
579 # and so celebrated two Sundays that week. See: Ahllund T (tr Hallamaa P).
580 # From the memoirs of a Finnish workman. Alaska History. 2006 Fall;21(2):1-25.
581 # http://alaskahistoricalsociety.org/wp-content/uploads/2016/12/Ahllund-2006-Memoirs-of-a-Finnish-Workman.pdf
582 # Include only the time zone part of this transition, ignoring the switch
583 # from Julian to Gregorian, since we can't represent the Julian calendar.
585 # As far as we know, of the locations mentioned below only Sitka was
586 # permanently inhabited in 1867 by anyone using either calendar.
587 # (Yakutat was colonized by the Russians in 1799, but the settlement was
588 # destroyed in 1805 by a Yakutat-kon war party.) Many of Alaska's inhabitants
589 # were unaware of the US acquisition of Alaska, much less of any calendar or
590 # time change. However, the Russian-influenced part of Alaska did observe
591 # Russian time, and it is more accurate to model this than to ignore it.
592 # The database format requires an exact transition time; use the Russian
593 # salute as a somewhat-arbitrary time for the formal transfer of control for
594 # all of Alaska. Sitka's UTC offset is -9:01:13; adjust its 15:30 to the
595 # local times of other Alaskan locations so that they change simultaneously.
597 # From Paul Eggert (2014-07-18):
598 # One opinion of the early-1980s turmoil in Alaska over time zones and
599 # daylight saving time appeared as graffiti on a Juneau airport wall:
600 # "Welcome to Juneau. Please turn your watch back to the 19th century."
601 # See: Turner W. Alaska's four time zones now two. NY Times 1983-11-01.
602 # http://www.nytimes.com/1983/11/01/us/alaska-s-four-time-zones-now-two.html
604 # Steve Ferguson (2011-01-31) referred to the following source:
605 # Norris F. Keeping time in Alaska: national directives, local response.
606 # Alaska History 2001;16(1-2).
607 # http://alaskahistoricalsociety.org/discover-alaska/glimpses-of-the-past/keeping-time-in-alaska/
609 # From Arthur David Olson (2011-02-01):
610 # Here's database-relevant material from the 2001 "Alaska History" article:
612 # On September 20 [1979]...DOT...officials decreed that on April 27,
613 # 1980, Juneau and other nearby communities would move to Yukon Time.
614 # Sitka, Petersburg, Wrangell, and Ketchikan, however, would remain on
617 # ...on September 22, 1980, DOT Secretary Neil E. Goldschmidt rescinded the
618 # Department's September 1979 decision. Juneau and other communities in
619 # northern Southeast reverted to Pacific Time on October 26.
621 # On October 28 [1983]...the Metlakatla Indian Community Council voted
622 # unanimously to keep the reservation on Pacific Time.
624 # According to DOT official Joanne Petrie, Indian reservations are not
625 # bound to follow time zones imposed by neighboring jurisdictions.
627 # (The last is consistent with how the database now handles the Navajo
630 # From Arthur David Olson (2011-02-09):
631 # I just spoke by phone with a staff member at the Metlakatla Indian
632 # Community office (using contact information available at
633 # http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?Comm_Boro_name=Metlakatla
634 # It's shortly after 1:00 here on the east coast of the United States;
635 # the staffer said it was shortly after 10:00 there. When I asked whether
636 # that meant they were on Pacific time, they said no - they were on their
637 # own time. I asked about daylight saving; they said it wasn't used. I
638 # did not inquire about practices in the past.
640 # From Arthur David Olson (2011-08-17):
641 # For lack of better information, assume that Metlakatla's
642 # abandonment of use of daylight saving resulted from the 1983 vote.
644 # From Steffen Thorsen (2015-11-09):
645 # It seems Metlakatla did go off PST on Sunday, November 1, changing
646 # their time to AKST and are going to follow Alaska's DST, switching
647 # between AKST and AKDT from now on....
648 # https://www.krbd.org/2015/10/30/annette-island-times-they-are-a-changing/
650 # From Ryan Stanley (2018-11-06):
651 # The Metlakatla community in Alaska has decided not to change its
652 # clock back an hour starting on November 4th, 2018 (day before yesterday).
653 # They will be gmtoff=-28800 year-round.
654 # https://www.facebook.com/141055983004923/photos/pb.141055983004923.-2207520000.1541465673./569081370202380/
656 # From Paul Eggert (2018-12-16):
657 # In a 2018-12-11 special election, Metlakatla voted to go back to
658 # Alaska time (including daylight saving time) starting next year.
659 # https://www.krbd.org/2018/12/12/metlakatla-to-follow-alaska-standard-time-allow-liquor-sales/
661 # From Ryan Stanley (2019-01-11):
662 # The community will be changing back on the 20th of this month...
663 # From Tim Parenti (2019-01-11):
664 # Per an announcement on the Metlakatla community's official Facebook page, the
665 # "fall back" will be on Sunday 2019-01-20 at 02:00:
666 # https://www.facebook.com/141055983004923/photos/607150969728753/
667 # So they won't be waiting for Alaska to join them on 2019-03-10, but will
668 # rather change their clocks twice in seven weeks.
670 # Zone NAME STDOFF RULES FORMAT [UNTIL]
671 Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32
672 -8:57:41 - LMT 1900 Aug 20 12:00
676 -8:00 US P%sT 1980 Apr 27 2:00
677 -9:00 US Y%sT 1980 Oct 26 2:00
678 -8:00 US P%sT 1983 Oct 30 2:00
679 -9:00 US Y%sT 1983 Nov 30
681 Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30
682 -9:01:13 - LMT 1900 Aug 20 12:00
686 -8:00 US P%sT 1983 Oct 30 2:00
687 -9:00 US Y%sT 1983 Nov 30
689 Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55
690 -8:46:18 - LMT 1900 Aug 20 12:00
694 -8:00 US P%sT 1983 Oct 30 2:00
695 -8:00 - PST 2015 Nov 1 2:00
696 -9:00 US AK%sT 2018 Nov 4 2:00
697 -8:00 - PST 2019 Jan 20 2:00
699 Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 15:12:18
700 -9:18:55 - LMT 1900 Aug 20 12:00
704 -9:00 US Y%sT 1983 Nov 30
706 Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37
707 -9:59:36 - LMT 1900 Aug 20 12:00
709 -10:00 US A%sT 1967 Apr
711 -10:00 US AH%sT 1983 Oct 30 2:00
712 -9:00 US Y%sT 1983 Nov 30
714 Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35
715 -11:01:38 - LMT 1900 Aug 20 12:00
718 -11:00 - NST 1967 Apr
720 -11:00 US B%sT 1983 Oct 30 2:00
721 -9:00 US Y%sT 1983 Nov 30
723 Zone America/Adak 12:13:22 - LMT 1867 Oct 19 12:44:35
724 -11:46:38 - LMT 1900 Aug 20 12:00
727 -11:00 - NST 1967 Apr
729 -11:00 US B%sT 1983 Oct 30 2:00
730 -10:00 US AH%sT 1983 Nov 30
732 # The following switches don't make our 1970 cutoff.
734 # Kiska observed Tokyo date and time during Japanese occupation from
735 # 1942-06-06 to 1943-07-29, and similarly for Attu from 1942-06-07 to
736 # 1943-05-29 (all dates American). Both islands are now uninhabited.
738 # Shanks writes that part of southwest Alaska (e.g. Aniak)
739 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
740 # and another part (e.g. Akiak) made the same switch five weeks later.
742 # From David Flater (2004-11-09):
743 # In e-mail, 2004-11-02, Ray Hudson, historian/liaison to the Unalaska
744 # Historic Preservation Commission, provided this information, which
745 # suggests that Unalaska deviated from statutory time from early 1967
746 # possibly until 1983:
748 # Minutes of the Unalaska City Council Meeting, January 10, 1967:
749 # "Except for St. Paul and Akutan, Unalaska is the only important
750 # location not on Alaska Standard Time. The following resolution was
751 # made by William Robinson and seconded by Henry Swanson: Be it
752 # resolved that the City of Unalaska hereby goes to Alaska Standard
753 # Time as of midnight Friday, January 13, 1967 (1 A.M. Saturday,
754 # January 14, Alaska Standard Time.) This resolution was passed with
755 # three votes for and one against."
759 # From Arthur David Olson (2010-12-09):
760 # "Hawaiian Time" by Robert C. Schmitt and Doak C. Cox appears on pages 207-225
761 # of volume 26 of The Hawaiian Journal of History (1992). As of 2010-12-09,
762 # the article is available at
763 # https://evols.library.manoa.hawaii.edu/bitstream/10524/239/2/JL26215.pdf
764 # and indicates that standard time was adopted effective noon, January
765 # 13, 1896 (page 218), that in "1933, the Legislature decreed daylight
766 # saving for the period between the last Sunday of each April and the
767 # last Sunday of each September, but less than a month later repealed the
768 # act," (page 220), that year-round daylight saving time was in effect
769 # from 1942-02-09 to 1945-09-30 (page 221, with no time of day given for
770 # when clocks changed) and that clocks were changed by 30 minutes
771 # effective the second Sunday of June, 1947 (page 219, with no time of
772 # day given for when clocks changed). A footnote for the 1933 changes
773 # cites Session Laws of Hawaii 1933, "Act. 90 (approved 26 Apr. 1933)
774 # and Act 163 (approved 21 May 1933)."
776 # From Arthur David Olson (2011-01-19):
777 # The following is from "Laws of the Territory of Hawaii Passed by the
778 # Seventeenth Legislature: Regular Session 1933," available (as of
779 # 2011-01-19) at American University's Pence Law Library. Page 85: "Act
780 # 90...At 2 o'clock ante meridian of the last Sunday in April of each
781 # year, the standard time of this Territory shall be advanced one
782 # hour...This Act shall take effect upon its approval. Approved this 26th
783 # day of April, A. D. 1933. LAWRENCE M JUDD, Governor of the Territory of
784 # Hawaii." Page 172: "Act 163...Act 90 of the Session Laws of 1933 is
785 # hereby repealed...This Act shall take effect upon its approval, upon
786 # which date the standard time of this Territory shall be restored to
787 # that existing immediately prior to the taking effect of said Act 90.
788 # Approved this 21st day of May, A. D. 1933. LAWRENCE M. JUDD, Governor
789 # of the Territory of Hawaii."
791 # Note that 1933-05-21 was a Sunday.
792 # We're left to guess the time of day when Act 163 was approved; guess noon.
794 # Zone NAME STDOFF RULES FORMAT [UNTIL]
795 Zone Pacific/Honolulu -10:31:26 - LMT 1896 Jan 13 12:00
796 -10:30 - HST 1933 Apr 30 2:00
797 -10:30 1:00 HDT 1933 May 21 12:00
798 -10:30 US H%sT 1947 Jun 8 2:00
801 # Now we turn to US areas that have diverged from the consensus since 1970.
803 # Arizona mostly uses MST.
805 # From Paul Eggert (2002-10-20):
807 # The information in the rest of this paragraph is derived from the
808 # Daylight Saving Time web page
809 # <http://www.dlapr.lib.az.us/links/daylight.htm> (2002-01-23)
810 # maintained by the Arizona State Library, Archives and Public Records.
811 # Between 1944-01-01 and 1944-04-01 the State of Arizona used standard
812 # time, but by federal law railroads, airlines, bus lines, military
813 # personnel, and some engaged in interstate commerce continued to
814 # observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix
815 # Gazette says that was the date the law changed, and that 04-01 was
816 # the date the state's clocks would change. In 1945 the State of
817 # Arizona used standard time all year, again with exceptions only as
818 # mandated by federal law. Arizona observed DST in 1967, but Arizona
819 # Laws 1968, ch. 183 (effective 1968-03-21) repealed DST.
821 # Shanks says the 1944 experiment came to an end on 1944-03-17.
822 # Go with the Arizona State Library instead.
824 # Zone NAME STDOFF RULES FORMAT [UNTIL]
825 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 19:00u
826 -7:00 US M%sT 1944 Jan 1 0:01
827 -7:00 - MST 1944 Apr 1 0:01
828 -7:00 US M%sT 1944 Oct 1 0:01
830 -7:00 US M%sT 1968 Mar 21
833 # From Arthur David Olson (1988-02-13):
834 # A writer from the Inter Tribal Council of Arizona, Inc.,
835 # notes in private correspondence dated 1987-12-28 that "Presently, only the
836 # Navajo Nation participates in the Daylight Saving Time policy, due to its
837 # large size and location in three states." (The "only" means that other
838 # tribal nations don't use DST.)
840 # From Paul Eggert (2013-08-26):
841 # See America/Denver for a zone appropriate for the Navajo Nation.
843 # Southern Idaho (Ada, Adams, Bannock, Bear Lake, Bingham, Blaine,
844 # Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark,
845 # Custer, Elmore, Franklin, Fremont, Gem, Gooding, Jefferson, Jerome,
846 # Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power,
847 # Teton, Twin Falls, Valley, Washington counties, and the southern
848 # quarter of Idaho county) and eastern Oregon (most of Malheur County)
849 # switched four weeks late in 1974.
851 # Zone NAME STDOFF RULES FORMAT [UNTIL]
852 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 20:00u
853 -8:00 US P%sT 1923 May 13 2:00
855 -7:00 - MST 1974 Feb 3 2:00
860 # For a map of Indiana's time zone regions, see:
861 # https://en.wikipedia.org/wiki/Time_in_Indiana
863 # From Paul Eggert (2018-11-30):
864 # A brief but entertaining history of time in Indiana describes a 1949 debate
865 # in the Indiana House where city legislators (who favored "fast time")
866 # tussled with farm legislators (who didn't) over a bill to outlaw DST:
867 # "Lacking enough votes, the city faction tries to filibuster until time runs
868 # out on the session at midnight, but rural champion Rep. Herbert Copeland,
869 # R-Madison, leans over the gallery railing and forces the official clock
870 # back to 9 p.m., breaking it in the process. The clock sticks on 9 as the
871 # debate rages on into the night. The filibuster finally dies out and the
872 # bill passes, while outside the chamber, clocks read 3:30 a.m. In the end,
873 # it doesn't matter which side won. The law has no enforcement powers and
874 # is simply ignored by fast-time communities."
875 # How Indiana went from 'God's time' to split zones and daylight-saving.
876 # Indianapolis Star. 2018-11-27 14:58 -05.
877 # https://www.indystar.com/story/news/politics/2018/11/27/indianapolis-indiana-time-zone-history-central-eastern-daylight-savings-time/2126300002/
879 # From Paul Eggert (2007-08-17):
880 # Since 1970, most of Indiana has been like America/Indiana/Indianapolis,
881 # with the following exceptions:
883 # - Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer,
884 # Vanderburgh, and Warrick counties have been like America/Chicago.
886 # - Dearborn and Ohio counties have been like America/New_York.
888 # - Clark, Floyd, and Harrison counties have been like
889 # America/Kentucky/Louisville.
891 # - Crawford, Daviess, Dubois, Knox, Martin, Perry, Pike, Pulaski, Starke,
892 # and Switzerland counties have their own time zone histories as noted below.
894 # Shanks partitioned Indiana into 345 regions, each with its own time history,
895 # and wrote "Even newspaper reports present contradictory information."
896 # Those Hoosiers! Such a flighty and changeable people!
897 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
899 # Other than Indianapolis, the Indiana place names are so nondescript
900 # that they would be ambiguous if we left them at the 'America' level.
901 # So we reluctantly put them all in a subdirectory 'America/Indiana'.
903 # From Paul Eggert (2014-06-26):
904 # https://www.federalregister.gov/articles/2006/01/20/06-563/standard-time-zone-boundary-in-the-state-of-indiana
905 # says "DOT is relocating the time zone boundary in Indiana to move Starke,
906 # Pulaski, Knox, Daviess, Martin, Pike, Dubois, and Perry Counties from the
907 # Eastern Time Zone to the Central Time Zone.... The effective date of
908 # this rule is 2 a.m. EST Sunday, April 2, 2006, which is the
909 # changeover date from standard time to Daylight Saving Time."
910 # Strictly speaking, this meant the affected counties changed their
911 # clocks twice that night, but this obviously was in error. The intent
912 # was that 01:59:59 EST be followed by 02:00:00 CDT.
914 # From Gwillim Law (2007-02-10):
915 # The Associated Press has been reporting that Pulaski County, Indiana is
916 # going to switch from Central to Eastern Time on March 11, 2007....
917 # http://www.indystar.com/apps/pbcs.dll/article?AID=/20070207/LOCAL190108/702070524/0/LOCAL
919 # Rule NAME FROM TO - IN ON AT SAVE LETTER
920 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
921 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
922 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
923 # Zone NAME STDOFF RULES FORMAT [UNTIL]
924 Zone America/Indiana/Indianapolis -5:44:38 - LMT 1883 Nov 18 18:00u
926 -6:00 Indianapolis C%sT 1942
928 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
929 -5:00 - EST 1957 Sep 29 2:00
930 -6:00 - CST 1958 Apr 27 2:00
936 # Eastern Crawford County, Indiana, left its clocks alone in 1974,
937 # as well as from 1976 through 2005.
938 # Rule NAME FROM TO - IN ON AT SAVE LETTER
939 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
940 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
941 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
942 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
943 # Zone NAME STDOFF RULES FORMAT [UNTIL]
944 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 18:00u
946 -6:00 Marengo C%sT 1961 Apr 30 2:00
948 -5:00 US E%sT 1974 Jan 6 2:00
949 -6:00 1:00 CDT 1974 Oct 27 2:00
954 # Daviess, Dubois, Knox, and Martin Counties, Indiana,
955 # switched from eastern to central time in April 2006, then switched back
957 # Rule NAME FROM TO - IN ON AT SAVE LETTER
958 Rule Vincennes 1946 only - Apr lastSun 2:00 1:00 D
959 Rule Vincennes 1946 only - Sep lastSun 2:00 0 S
960 Rule Vincennes 1953 1954 - Apr lastSun 2:00 1:00 D
961 Rule Vincennes 1953 1959 - Sep lastSun 2:00 0 S
962 Rule Vincennes 1955 only - May 1 0:00 1:00 D
963 Rule Vincennes 1956 1963 - Apr lastSun 2:00 1:00 D
964 Rule Vincennes 1960 only - Oct lastSun 2:00 0 S
965 Rule Vincennes 1961 only - Sep lastSun 2:00 0 S
966 Rule Vincennes 1962 1963 - Oct lastSun 2:00 0 S
967 # Zone NAME STDOFF RULES FORMAT [UNTIL]
968 Zone America/Indiana/Vincennes -5:50:07 - LMT 1883 Nov 18 18:00u
970 -6:00 Vincennes C%sT 1964 Apr 26 2:00
973 -5:00 - EST 2006 Apr 2 2:00
974 -6:00 US C%sT 2007 Nov 4 2:00
977 # Perry County, Indiana, switched from eastern to central time in April 2006.
978 # From Alois Treindl (2019-07-09):
979 # The Indianapolis News, Friday 27 October 1967 states that Perry County
980 # returned to CST. It went again to EST on 27 April 1969, as documented by the
981 # Indianapolis star of Saturday 26 April.
982 # Rule NAME FROM TO - IN ON AT SAVE LETTER
983 Rule Perry 1955 only - May 1 0:00 1:00 D
984 Rule Perry 1955 1960 - Sep lastSun 2:00 0 S
985 Rule Perry 1956 1963 - Apr lastSun 2:00 1:00 D
986 Rule Perry 1961 1963 - Oct lastSun 2:00 0 S
987 # Zone NAME STDOFF RULES FORMAT [UNTIL]
988 Zone America/Indiana/Tell_City -5:47:03 - LMT 1883 Nov 18 18:00u
990 -6:00 Perry C%sT 1964 Apr 26 2:00
991 -5:00 - EST 1967 Oct 29 2:00
992 -6:00 US C%sT 1969 Apr 27 2:00
994 -5:00 - EST 2006 Apr 2 2:00
997 # Pike County, Indiana moved from central to eastern time in 1977,
998 # then switched back in 2006, then switched back again in 2007.
999 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1000 Rule Pike 1955 only - May 1 0:00 1:00 D
1001 Rule Pike 1955 1960 - Sep lastSun 2:00 0 S
1002 Rule Pike 1956 1964 - Apr lastSun 2:00 1:00 D
1003 Rule Pike 1961 1964 - Oct lastSun 2:00 0 S
1004 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1005 Zone America/Indiana/Petersburg -5:49:07 - LMT 1883 Nov 18 18:00u
1007 -6:00 Pike C%sT 1965 Apr 25 2:00
1008 -5:00 - EST 1966 Oct 30 2:00
1009 -6:00 US C%sT 1977 Oct 30 2:00
1010 -5:00 - EST 2006 Apr 2 2:00
1011 -6:00 US C%sT 2007 Nov 4 2:00
1014 # Starke County, Indiana moved from central to eastern time in 1991,
1015 # then switched back in 2006.
1016 # From Arthur David Olson (1991-10-28):
1017 # An article on page A3 of the Sunday, 1991-10-27 Washington Post
1018 # notes that Starke County switched from Central time to Eastern time as of
1020 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1021 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
1022 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
1023 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
1024 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
1025 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
1026 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1027 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 18:00u
1029 -6:00 Starke C%sT 1962 Apr 29 2:00
1030 -5:00 - EST 1963 Oct 27 2:00
1031 -6:00 US C%sT 1991 Oct 27 2:00
1032 -5:00 - EST 2006 Apr 2 2:00
1035 # Pulaski County, Indiana, switched from eastern to central time in
1036 # April 2006 and then switched back in March 2007.
1037 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1038 Rule Pulaski 1946 1960 - Apr lastSun 2:00 1:00 D
1039 Rule Pulaski 1946 1954 - Sep lastSun 2:00 0 S
1040 Rule Pulaski 1955 1956 - Oct lastSun 2:00 0 S
1041 Rule Pulaski 1957 1960 - Sep lastSun 2:00 0 S
1042 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1043 Zone America/Indiana/Winamac -5:46:25 - LMT 1883 Nov 18 18:00u
1045 -6:00 Pulaski C%sT 1961 Apr 30 2:00
1048 -5:00 - EST 2006 Apr 2 2:00
1049 -6:00 US C%sT 2007 Mar 11 2:00
1052 # Switzerland County, Indiana, did not observe DST from 1973 through 2005.
1053 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1054 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 18:00u
1055 -6:00 US C%sT 1954 Apr 25 2:00
1061 # From Paul Eggert (2018-03-20):
1062 # The Louisville & Nashville Railroad's 1883-11-18 change occurred at
1063 # 10:00 old local time; train were supposed to come to a standstill
1064 # for precisely 18 minutes. See Bartky Fig. 1 (page 50). It is not
1065 # clear how this matched civil time in Louisville, so for now continue
1066 # to assume Louisville switched at noon new local time, like New York.
1068 # From Michael Deckers (2019-08-06):
1069 # From the contemporary source given by Alois Treindl,
1070 # the switch in Louisville on 1946-04-28 was on 00:01
1071 # From Paul Eggert (2019-08-26):
1072 # That source was the Louisville Courier-Journal, 1946-04-27, p 4.
1073 # Shanks gives 02:00 for all 20th-century transition times in Louisville.
1074 # Evidently this is wrong for spring 1946. Although also likely wrong
1075 # for other dates, we have no data.
1077 # Part of Kentucky left its clocks alone in 1974.
1078 # This also includes Clark, Floyd, and Harrison counties in Indiana.
1079 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1080 Rule Louisville 1921 only - May 1 2:00 1:00 D
1081 Rule Louisville 1921 only - Sep 1 2:00 0 S
1082 Rule Louisville 1941 only - Apr lastSun 2:00 1:00 D
1083 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
1084 Rule Louisville 1946 only - Apr lastSun 0:01 1:00 D
1085 Rule Louisville 1946 only - Jun 2 2:00 0 S
1086 Rule Louisville 1950 1961 - Apr lastSun 2:00 1:00 D
1087 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
1088 Rule Louisville 1956 1961 - Oct lastSun 2:00 0 S
1089 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1090 Zone America/Kentucky/Louisville -5:43:02 - LMT 1883 Nov 18 18:00u
1092 -6:00 Louisville C%sT 1942
1094 -6:00 Louisville C%sT 1961 Jul 23 2:00
1096 -5:00 US E%sT 1974 Jan 6 2:00
1097 -6:00 1:00 CDT 1974 Oct 27 2:00
1100 # Wayne County, Kentucky
1102 # From Lake Cumberland LIFE
1103 # http://www.lake-cumberland.com/life/archive/news990129time.shtml
1104 # (1999-01-29) via WKYM-101.7:
1105 # Clinton County has joined Wayne County in asking the DoT to change from
1106 # the Central to the Eastern time zone.... The Wayne County government made
1107 # the same request in December. And while Russell County officials have not
1108 # taken action, the majority of respondents to a poll conducted there in
1109 # August indicated they would like to change to "fast time" also.
1110 # The three Lake Cumberland counties are the farthest east of any U.S.
1111 # location in the Central time zone.
1113 # From Rich Wales (2000-08-29):
1114 # After prolonged debate, and despite continuing deep differences of opinion,
1115 # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern
1116 # (-0500) time. They won't "fall back" this year. See Sara Shipley,
1117 # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400).
1119 # From Paul Eggert (2001-07-16):
1120 # The final rule was published in the
1121 # Federal Register 65, 160 (2000-08-17), pp 50154-50158.
1122 # https://www.gpo.gov/fdsys/pkg/FR-2000-08-17/html/00-20854.htm
1124 Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 18:00u
1127 -6:00 US C%sT 2000 Oct 29 2:00
1131 # From Rives McDow (2000-08-30):
1132 # Here ... are all the changes in the US since 1985.
1133 # Kearny County, KS (put all of county on central;
1134 # previously split between MST and CST) ... 1990-10
1135 # Starke County, IN (from CST to EST) ... 1991-10
1136 # Oliver County, ND (from MST to CST) ... 1992-10
1137 # West Wendover, NV (from PST TO MST) ... 1999-10
1138 # Wayne County, KY (from CST to EST) ... 2000-10
1140 # From Paul Eggert (2001-07-17):
1141 # We don't know where the line used to be within Kearny County, KS,
1142 # so omit that change for now.
1143 # See America/Indiana/Knox for the Starke County, IN change.
1144 # See America/North_Dakota/Center for the Oliver County, ND change.
1145 # West Wendover, NV officially switched from Pacific to mountain time on
1146 # 1999-10-31. See the
1147 # Federal Register 64, 203 (1999-10-21), pp 56705-56707.
1148 # https://www.gpo.gov/fdsys/pkg/FR-1999-10-21/html/99-27240.htm
1149 # However, the Federal Register says that West Wendover already operated
1150 # on mountain time, and the rule merely made this official;
1151 # hence a separate tz entry is not needed.
1155 # From Bob Devine (1988-01-28):
1156 # Michigan didn't observe DST from 1968 to 1973.
1158 # From Paul Eggert (1999-03-31):
1159 # Shanks writes that Michigan started using standard time on 1885-09-18,
1160 # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01)
1163 # local time until 1900 when the City Council decreed that clocks should
1164 # be put back twenty-eight minutes to Central Standard Time. Half the
1165 # city obeyed, half refused. After considerable debate, the decision
1166 # was rescinded and the city reverted to Sun time. A derisive offer to
1167 # erect a sundial in front of the city hall was referred to the
1168 # Committee on Sewers. Then, in 1905, Central time was adopted
1171 # This story is too entertaining to be false, so go with Howse over Shanks.
1173 # From Paul Eggert (2001-03-06):
1174 # Garland (1927) writes "Cleveland and Detroit advanced their clocks
1175 # one hour in 1914." This change is not in Shanks. We have no more
1176 # info, so omit this for now.
1178 # From Paul Eggert (2019-07-06):
1179 # Due to a complicated set of legal maneuvers, in 1967 Michigan did
1180 # not start daylight saving time when the rest of the US did.
1181 # Instead, it began DST on Jun 14 at 00:01. This was big news:
1182 # the Detroit Free Press reported it at the top of Page 1 on
1183 # 1967-06-14, in an article "State Adjusting to Switch to Fast Time"
1184 # by Gary Blonston, above an article about Thurgood Marshall's
1185 # confirmation to the US Supreme Court. Although Shanks says Detroit
1186 # observed DST until 1967-10-29 00:01, that time of day seems to be
1187 # incorrect, as the Free Press later said DST ended in Michigan at the
1188 # same time as the rest of the US. Also, although Shanks reports no DST in
1189 # Detroit in 1968, it did observe DST that year; in the November 1968
1190 # election Michigan voters narrowly repealed DST, effective 1969.
1192 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
1193 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1194 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
1195 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
1196 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1197 Zone America/Detroit -5:32:11 - LMT 1905
1198 -6:00 - CST 1915 May 15 2:00
1201 -5:00 Detroit E%sT 1967 Jun 14 0:01
1205 -5:00 - EST 1975 Apr 27 2:00
1208 # Dickinson, Gogebic, Iron, and Menominee Counties, Michigan,
1209 # switched from EST to CST/CDT in 1973.
1210 # Rule NAME FROM TO - IN ON AT SAVE LETTER
1211 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
1212 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
1213 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
1214 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
1215 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1216 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
1218 -6:00 Menominee C%sT 1969 Apr 27 2:00
1219 -5:00 - EST 1973 Apr 29 2:00
1223 # administered by the US Fish and Wildlife Service
1224 # claimed by US under the provisions of the 1856 Guano Islands Act
1225 # also claimed by Haiti
1226 # occupied 1857/1900 by the Navassa Phosphate Co
1227 # US lighthouse 1917/1996-09
1228 # currently uninhabited
1229 # see Mark Fineman, "An Isle Rich in Guano and Discord",
1230 # _Los Angeles Times_ (1998-11-10), A1, A10; it cites
1231 # Jimmy Skaggs, _The Great Guano Rush_ (1994).
1233 ################################################################################
1236 # From Paul Eggert (2017-02-10):
1238 # Unless otherwise specified, the source for data through 1990 is:
1239 # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition),
1240 # San Diego: ACS Publications, Inc. (2003).
1241 # Unfortunately this book contains many errors and cites no sources.
1243 # Many years ago Gwillim Law wrote that a good source
1244 # for time zone data was the International Air Transport
1245 # Association's Standard Schedules Information Manual (IATA SSIM),
1246 # published semiannually. Law sent in several helpful summaries
1247 # of the IATA's data after 1990. Except where otherwise noted,
1248 # IATA SSIM is the source for entries after 1990.
1250 # Other sources occasionally used include:
1252 # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94
1253 # <https://www.jstor.org/stable/1774359>.
1255 # Pearce C. The Great Daylight Saving Time Controversy.
1256 # Australian Ebook Publisher. 2017. ISBN 978-1-925516-96-8.
1258 # Edward W. Whitman, World Time Differences,
1259 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated),
1260 # which I found in the UCLA library.
1262 # William Willett, The Waste of Daylight, 19th edition
1263 # <http://cs.ucla.edu/~eggert/The-Waste-of-Daylight-19th.pdf>
1266 # See the 'europe' file for Greenland.
1270 # From Alain LaBonté (1994-11-14):
1271 # I post here the time zone abbreviations standardized in Canada
1272 # for both English and French in the CAN/CSA-Z234.4-89 standard....
1274 # UTC Standard time Daylight saving time
1275 # offset French English French English
1279 # -4 HNA AST HAE EDT
1280 # -5 HNE EST HAC CDT
1281 # -6 HNC CST HAR MDT
1282 # -7 HNR MST HAP PDT
1283 # -8 HNP PST HAY YDT
1286 # HN: Heure Normale ST: Standard Time
1287 # HA: Heure Avancée DT: Daylight saving Time
1289 # A: de l'Atlantique Atlantic
1290 # C: du Centre Central
1291 # E: de l'Est Eastern
1294 # P: du Pacifique Pacific
1299 # From Paul Eggert (1994-11-22):
1300 # Alas, this sort of thing must be handled by localization software.
1302 # Unless otherwise specified, the data entries for Canada are all from Shanks
1305 # From Chris Walton (2006-04-01, 2006-04-25, 2006-06-26, 2007-01-31,
1307 # The British Columbia government announced yesterday that it will
1308 # adjust daylight savings next year to align with changes in the
1309 # U.S. and the rest of Canada....
1310 # https://archive.news.gov.bc.ca/releases/news_releases_2005-2009/2006AG0014-000330.htm
1313 # Daylight saving time will be extended by four weeks starting in 2007....
1314 # https://www.novascotia.ca/just/regulations/rg2/2006/ma1206.pdf
1316 # [For New Brunswick] the new legislation dictates that the time change is to
1317 # be done at 02:00 instead of 00:01.
1318 # https://www.gnb.ca/0062/acts/BBA-2006/Chap-19.pdf
1320 # Manitoba has traditionally changed the clock every fall at 03:00.
1321 # As of 2006, the transition is to take place one hour earlier at 02:00.
1322 # https://web2.gov.mb.ca/laws/statutes/ccsm/o030e.php
1324 # [Alberta, Ontario, Quebec] will follow US rules.
1325 # http://www.qp.gov.ab.ca/documents/spring/CH03_06.CFM
1326 # http://www.e-laws.gov.on.ca/DBLaws/Source/Regs/English/2006/R06111_e.htm
1327 # http://www2.publicationsduquebec.gouv.qc.ca/dynamicSearch/telecharge.php?type=5&file=2006C39A.PDF
1329 # P.E.I. will follow US rules....
1330 # http://www.assembly.pe.ca/bills/pdf_chapter/62/3/chapter-41.pdf
1332 # Province of Newfoundland and Labrador....
1333 # http://www.hoa.gov.nl.ca/hoa/bills/Bill0634.htm
1336 # https://www.gov.yk.ca/legislation/regs/oic2006_127.pdf
1338 # N.W.T. will follow US rules. Whoever maintains the government web site
1339 # does not seem to believe in bookmarks. To see the news release, click the
1340 # following link and search for "Daylight Savings Time Change". Press the
1341 # "Daylight Savings Time Change" link; it will fire off a popup using
1343 # http://www.exec.gov.nt.ca/currentnews/currentPR.asp?mode=archive
1346 # An amendment to the Interpretation Act was registered on February 19/2007....
1347 # http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf
1349 # From Paul Eggert (2014-10-18):
1350 # H. David Matthews and Mary Vincent's map
1351 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
1352 # http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp
1353 # contains detailed boundaries for regions observing nonstandard
1354 # time and daylight saving time arrangements in Canada circa 1998.
1356 # National Research Council Canada maintains info about time zones and DST.
1357 # https://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html
1358 # https://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5
1359 # Its unofficial information is often taken from Matthews and Vincent.
1361 # From Paul Eggert (2006-06-27):
1362 # For now, assume all of DST-observing Canada will fall into line with the
1365 # From Chris Walton (2011-12-01)
1366 # In the first of Tammy Hardwick's articles
1367 # http://www.ilovecreston.com/?p=articles&t=spec&ar=260
1368 # she quotes the Friday November 1/1918 edition of the Creston Review.
1369 # The quote includes these two statements:
1370 # 'Sunday the CPR went back to the old system of time...'
1371 # '... The daylight saving scheme was dropped all over Canada at the same time,'
1372 # These statements refer to a transition from daylight time to standard time
1373 # that occurred nationally on Sunday October 27/1918. This transition was
1374 # also documented in the Saturday October 26/1918 edition of the Toronto Star.
1376 # In light of that evidence, we alter the date from the earlier believed
1377 # Oct 31, to Oct 27, 1918 (and Sunday is a more likely transition day
1378 # than Thursday) in all Canadian rulesets.
1380 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1381 Rule Canada 1918 only - Apr 14 2:00 1:00 D
1382 Rule Canada 1918 only - Oct 27 2:00 0 S
1383 Rule Canada 1942 only - Feb 9 2:00 1:00 W # War
1384 Rule Canada 1945 only - Aug 14 23:00u 1:00 P # Peace
1385 Rule Canada 1945 only - Sep 30 2:00 0 S
1386 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
1387 Rule Canada 1974 2006 - Oct lastSun 2:00 0 S
1388 Rule Canada 1987 2006 - Apr Sun>=1 2:00 1:00 D
1389 Rule Canada 2007 max - Mar Sun>=8 2:00 1:00 D
1390 Rule Canada 2007 max - Nov Sun>=1 2:00 0 S
1393 # Newfoundland and Labrador
1395 # From Paul Eggert (2017-10-14):
1396 # Legally Labrador should observe Newfoundland time; see:
1397 # McLeod J. Labrador time - legal or not? St. John's Telegram, 2017-10-07
1398 # http://www.thetelegram.com/news/local/labrador-time--legal-or-not-154860/
1399 # Matthews and Vincent (1998) write that the only part of Labrador
1400 # that follows the rules is the southeast corner, including Port Hope
1401 # Simpson and Mary's Harbour, but excluding, say, Black Tickle.
1403 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1404 Rule StJohns 1917 only - Apr 8 2:00 1:00 D
1405 Rule StJohns 1917 only - Sep 17 2:00 0 S
1406 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks & Pottenger.
1407 Rule StJohns 1919 only - May 5 23:00 1:00 D
1408 Rule StJohns 1919 only - Aug 12 23:00 0 S
1409 # For 1931-1935 Whitman gives Apr same date; go with Shanks & Pottenger.
1410 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
1411 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
1412 # For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks &
1414 Rule StJohns 1936 1941 - May Mon>=9 0:00 1:00 D
1415 Rule StJohns 1936 1941 - Oct Mon>=2 0:00 0 S
1416 # Whitman gives the following transitions:
1417 # 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07
1418 # but go with Shanks & Pottenger and assume they used Canadian rules.
1419 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
1420 # Apr 30 - Sep 24; go with Shanks & Pottenger.
1421 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
1422 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
1423 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
1424 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
1425 Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S
1426 # From Paul Eggert (2000-10-02):
1427 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
1428 # at 00:01 local time. For now, assume it started in 1987.
1430 # From Michael Pelley (2011-09-12):
1431 # We received today, Monday, September 12, 2011, notification that the
1432 # changes to the Newfoundland Standard Time Act have been proclaimed.
1433 # The change in the Act stipulates that the change from Daylight Savings
1434 # Time to Standard Time and from Standard Time to Daylight Savings Time
1435 # now occurs at 2:00AM.
1437 # http://www.assembly.nl.ca/legislation/sr/annualstatutes/2011/1106.chp.htm
1439 # MICHAEL PELLEY | Manager of Enterprise Architecture - Solution Delivery
1440 # Office of the Chief Information Officer
1442 # Government of Newfoundland & Labrador
1444 Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D
1445 Rule StJohns 1987 2006 - Oct lastSun 0:01 0 S
1446 Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD
1447 Rule StJohns 1989 2006 - Apr Sun>=1 0:01 1:00 D
1448 Rule StJohns 2007 2011 - Mar Sun>=8 0:01 1:00 D
1449 Rule StJohns 2007 2010 - Nov Sun>=1 0:01 0 S
1451 # St John's has an apostrophe, but Posix file names can't have apostrophes.
1452 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1453 Zone America/St_Johns -3:30:52 - LMT 1884
1454 -3:30:52 StJohns N%sT 1918
1455 -3:30:52 Canada N%sT 1919
1456 -3:30:52 StJohns N%sT 1935 Mar 30
1457 -3:30 StJohns N%sT 1942 May 11
1458 -3:30 Canada N%sT 1946
1459 -3:30 StJohns N%sT 2011 Nov
1462 # most of east Labrador
1464 # The name 'Happy Valley-Goose Bay' is too long; use 'Goose Bay'.
1465 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1466 Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay
1468 -3:30:52 Canada N%sT 1919
1469 -3:30:52 - NST 1935 Mar 30
1471 -3:30 StJohns N%sT 1942 May 11
1472 -3:30 Canada N%sT 1946
1473 -3:30 StJohns N%sT 1966 Mar 15 2:00
1474 -4:00 StJohns A%sT 2011 Nov
1478 # west Labrador, Nova Scotia, Prince Edward I,
1479 # Îles-de-la-Madeleine, Listuguj reserve
1481 # From Brian Inglis (2015-07-20):
1482 # From the historical weather station records available at:
1483 # https://weatherspark.com/history/28351/1971/Sydney-Nova-Scotia-Canada
1484 # Sydney shares the same time history as Glace Bay, so was
1485 # likely to be the same across the island....
1486 # Sydney, as the capital and most populous location, or Cape Breton, would
1487 # have been better names for the zone had we known this in 1996.
1489 # From Paul Eggert (2015-07-20):
1490 # Shanks & Pottenger write that since 1970 most of this region has been like
1491 # Halifax. Many locales did not observe peacetime DST until 1972;
1492 # the Cape Breton area, represented by Glace Bay, is the largest we know of
1493 # (Glace Bay was perhaps not the best name choice but no point changing now).
1494 # Shanks & Pottenger also write that Liverpool, NS was the only town
1495 # in Canada to observe DST in 1971 but not 1970; for now we'll assume
1498 # From Jeffery Nichols (2020-01-09):
1499 # America/Halifax ... also applies to Îles-de-la-Madeleine and the Listuguj
1500 # reserve in Quebec. Officially, this came into effect on January 1, 2007
1501 # (Legal Time Act, CQLR c T-5.1), but the legislative debates surrounding that
1502 # bill say that it is "accommodating the customs and practices" of those
1503 # regions, which suggests that they have always been in-line with Halifax.
1505 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1506 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
1507 Rule Halifax 1916 only - Oct 1 0:00 0 S
1508 Rule Halifax 1920 only - May 9 0:00 1:00 D
1509 Rule Halifax 1920 only - Aug 29 0:00 0 S
1510 Rule Halifax 1921 only - May 6 0:00 1:00 D
1511 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
1512 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
1513 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
1514 Rule Halifax 1923 only - Sep 4 0:00 0 S
1515 Rule Halifax 1924 only - Sep 15 0:00 0 S
1516 Rule Halifax 1925 only - Sep 28 0:00 0 S
1517 Rule Halifax 1926 only - May 16 0:00 1:00 D
1518 Rule Halifax 1926 only - Sep 13 0:00 0 S
1519 Rule Halifax 1927 only - May 1 0:00 1:00 D
1520 Rule Halifax 1927 only - Sep 26 0:00 0 S
1521 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
1522 Rule Halifax 1928 only - Sep 9 0:00 0 S
1523 Rule Halifax 1929 only - Sep 3 0:00 0 S
1524 Rule Halifax 1930 only - Sep 15 0:00 0 S
1525 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
1526 Rule Halifax 1932 only - May 1 0:00 1:00 D
1527 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
1528 Rule Halifax 1933 only - Oct 2 0:00 0 S
1529 Rule Halifax 1934 only - May 20 0:00 1:00 D
1530 Rule Halifax 1934 only - Sep 16 0:00 0 S
1531 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
1532 Rule Halifax 1935 only - Sep 30 0:00 0 S
1533 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
1534 Rule Halifax 1936 only - Sep 14 0:00 0 S
1535 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
1536 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
1537 Rule Halifax 1939 only - May 28 0:00 1:00 D
1538 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
1539 Rule Halifax 1946 1949 - Apr lastSun 2:00 1:00 D
1540 Rule Halifax 1946 1949 - Sep lastSun 2:00 0 S
1541 Rule Halifax 1951 1954 - Apr lastSun 2:00 1:00 D
1542 Rule Halifax 1951 1954 - Sep lastSun 2:00 0 S
1543 Rule Halifax 1956 1959 - Apr lastSun 2:00 1:00 D
1544 Rule Halifax 1956 1959 - Sep lastSun 2:00 0 S
1545 Rule Halifax 1962 1973 - Apr lastSun 2:00 1:00 D
1546 Rule Halifax 1962 1973 - Oct lastSun 2:00 0 S
1547 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1548 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
1549 -4:00 Halifax A%sT 1918
1550 -4:00 Canada A%sT 1919
1551 -4:00 Halifax A%sT 1942 Feb 9 2:00s
1552 -4:00 Canada A%sT 1946
1553 -4:00 Halifax A%sT 1974
1555 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
1556 -4:00 Canada A%sT 1953
1557 -4:00 Halifax A%sT 1954
1559 -4:00 Halifax A%sT 1974
1564 # From Paul Eggert (2007-01-31):
1565 # The Time Definition Act <http://www.gnb.ca/0062/PDF-acts/t-06.pdf>
1566 # says they changed at 00:01 through 2006, and
1567 # <http://www.canlii.org/nb/laws/sta/t-6/20030127/whole.html> makes it
1568 # clear that this was the case since at least 1993.
1569 # For now, assume it started in 1993.
1571 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1572 Rule Moncton 1933 1935 - Jun Sun>=8 1:00 1:00 D
1573 Rule Moncton 1933 1935 - Sep Sun>=8 1:00 0 S
1574 Rule Moncton 1936 1938 - Jun Sun>=1 1:00 1:00 D
1575 Rule Moncton 1936 1938 - Sep Sun>=1 1:00 0 S
1576 Rule Moncton 1939 only - May 27 1:00 1:00 D
1577 Rule Moncton 1939 1941 - Sep Sat>=21 1:00 0 S
1578 Rule Moncton 1940 only - May 19 1:00 1:00 D
1579 Rule Moncton 1941 only - May 4 1:00 1:00 D
1580 Rule Moncton 1946 1972 - Apr lastSun 2:00 1:00 D
1581 Rule Moncton 1946 1956 - Sep lastSun 2:00 0 S
1582 Rule Moncton 1957 1972 - Oct lastSun 2:00 0 S
1583 Rule Moncton 1993 2006 - Apr Sun>=1 0:01 1:00 D
1584 Rule Moncton 1993 2006 - Oct lastSun 0:01 0 S
1585 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1586 Zone America/Moncton -4:19:08 - LMT 1883 Dec 9
1587 -5:00 - EST 1902 Jun 15
1588 -4:00 Canada A%sT 1933
1589 -4:00 Moncton A%sT 1942
1590 -4:00 Canada A%sT 1946
1591 -4:00 Moncton A%sT 1973
1592 -4:00 Canada A%sT 1993
1593 -4:00 Moncton A%sT 2007
1598 # From Paul Eggert (2020-01-10):
1599 # See America/Toronto for most of Quebec, including Montreal.
1600 # See America/Halifax for the Îles de la Madeleine and the Listuguj reserve.
1601 # See America/Puerto_Rico for east of Natashquan.
1605 # From Mark Brader (2003-07-26):
1606 # [According to the Toronto Star] Orillia, Ontario, adopted DST
1607 # effective Saturday, 1912-06-22, 22:00; the article mentions that
1608 # Port Arthur (now part of Thunder Bay, Ontario) as well as Moose Jaw
1609 # have already done so. In Orillia DST was to run until Saturday,
1610 # 1912-08-31 (no time mentioned), but it was met with considerable
1611 # hostility from certain segments of the public, and was revoked after
1612 # only two weeks - I copied it as Saturday, 1912-07-07, 22:00, but
1613 # presumably that should be -07-06. (1912-06-19, -07-12; also letters
1616 # Kenora, Ontario, was to abandon DST on 1914-06-01 (-05-21).
1618 # From Paul Eggert (2017-07-08):
1619 # For more on Orillia, see: Daubs K. Bold attempt at daylight saving
1620 # time became a comic failure in Orillia. Toronto Star 2017-07-08.
1621 # https://www.thestar.com/news/insight/2017/07/08/bold-attempt-at-daylight-saving-time-became-a-comic-failure-in-orillia.html
1623 # From Mark Brader (2010-03-06):
1625 # In the (Toronto) Globe and Mail for Saturday, 1955-09-24, in the bottom
1626 # right corner of page 1, it says that Toronto will return to standard
1627 # time at 2 am Sunday morning (which agrees with the database), and that:
1629 # The one-hour setback will go into effect throughout most of Ontario,
1630 # except in areas like Windsor which remains on standard time all year.
1632 # ... I don't know if Windsor began observing DST when Detroit did,
1633 # or in 1974, or on some other date.
1635 # By the way, the article continues by noting that:
1637 # Some cities in the United States have pushed the deadline back
1638 # three weeks and will change over from daylight saving in October.
1640 # From Arthur David Olson (2010-07-17):
1642 # "Standard Time and Time Zones in Canada" appeared in
1643 # The Journal of The Royal Astronomical Society of Canada,
1644 # volume 26, number 2 (February 1932) and, as of 2010-07-17,
1646 # http://adsabs.harvard.edu/full/1932JRASC..26...49S
1648 # It includes the text below (starting on page 57):
1650 # A list of the places in Canada using daylight saving time would
1651 # require yearly revision. From information kindly furnished by
1652 # the provincial governments and by the postmasters in many cities
1653 # and towns, it is found that the following places used daylight sav-
1654 # ing in 1930. The information for the province of Quebec is definite,
1655 # for the other provinces only approximate:
1657 # Province Daylight saving time used
1658 # Prince Edward Island Not used.
1659 # Nova Scotia In Halifax only.
1660 # New Brunswick In St. John only.
1661 # Quebec In the following places:
1665 # St. Lambert Cap de la Madelèine
1666 # Verdun Loretteville
1667 # Westmount Richmond
1668 # Outremont St. Jérôme
1669 # Longueuil Greenfield Park
1671 # Chambly-Canton Beaulieu
1672 # Melbourne La Tuque
1673 # St. Théophile Buckingham
1674 # Ontario Used generally in the cities and towns along
1675 # the southerly part of the province. Not
1676 # used in the northwesterly part.
1677 # Manitoba Not used.
1678 # Saskatchewan In Regina only.
1680 # British Columbia Not used.
1682 # With some exceptions, the use of daylight saving may be said to be limited
1683 # to those cities and towns lying between Quebec city and Windsor, Ont.
1685 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1686 Rule Toronto 1919 only - Mar 30 23:30 1:00 D
1687 Rule Toronto 1919 only - Oct 26 0:00 0 S
1688 Rule Toronto 1920 only - May 2 2:00 1:00 D
1689 Rule Toronto 1920 only - Sep 26 0:00 0 S
1690 Rule Toronto 1921 only - May 15 2:00 1:00 D
1691 Rule Toronto 1921 only - Sep 15 2:00 0 S
1692 Rule Toronto 1922 1923 - May Sun>=8 2:00 1:00 D
1693 # Shanks & Pottenger say 1923-09-19; assume it's a typo and that "-16"
1695 Rule Toronto 1922 1926 - Sep Sun>=15 2:00 0 S
1696 Rule Toronto 1924 1927 - May Sun>=1 2:00 1:00 D
1697 Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S
1698 Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D
1699 Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D
1700 Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S
1701 Rule Toronto 1945 1946 - Sep lastSun 2:00 0 S
1702 Rule Toronto 1946 only - Apr lastSun 2:00 1:00 D
1703 Rule Toronto 1947 1949 - Apr lastSun 0:00 1:00 D
1704 Rule Toronto 1947 1948 - Sep lastSun 0:00 0 S
1705 Rule Toronto 1949 only - Nov lastSun 0:00 0 S
1706 Rule Toronto 1950 1973 - Apr lastSun 2:00 1:00 D
1707 Rule Toronto 1950 only - Nov lastSun 2:00 0 S
1708 Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S
1709 # Shanks & Pottenger say Toronto ended DST a week early in 1971,
1710 # namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this
1711 # is wrong, and that he had confirmed it by checking the 1971-10-30
1712 # Toronto Star, which said that DST was ending 1971-10-31 as usual.
1713 Rule Toronto 1957 1973 - Oct lastSun 2:00 0 S
1715 # The Bahamas match Toronto since 1970.
1717 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1718 Zone America/Toronto -5:17:32 - LMT 1895
1719 -5:00 Canada E%sT 1919
1720 -5:00 Toronto E%sT 1942 Feb 9 2:00s
1721 -5:00 Canada E%sT 1946
1722 -5:00 Toronto E%sT 1974
1724 # For Atikokan see America/Panama.
1729 # From Rob Douglas (2006-04-06):
1730 # the old Manitoba Time Act - as amended by Bill 2, assented to
1731 # March 27, 1987 ... said ...
1732 # "between two o'clock Central Standard Time in the morning of
1733 # the first Sunday of April of each year and two o'clock Central
1734 # Standard Time in the morning of the last Sunday of October next
1735 # following, one hour in advance of Central Standard Time."...
1736 # I believe that the English legislation [of the old time act] had
1737 # been assented to (March 22, 1967)....
1738 # Also, as far as I can tell, there was no order-in-council varying
1739 # the time of Daylight Saving Time for 2005 and so the provisions of
1740 # the 1987 version would apply - the changeover was at 2:00 Central
1741 # Standard Time (i.e. not until 3:00 Central Daylight Time).
1743 # From Paul Eggert (2006-04-10):
1744 # Shanks & Pottenger say Manitoba switched at 02:00 (not 02:00s)
1745 # starting 1966. Since 02:00s is clearly correct for 1967 on, assume
1746 # it was also 02:00s in 1966.
1748 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1749 Rule Winn 1916 only - Apr 23 0:00 1:00 D
1750 Rule Winn 1916 only - Sep 17 0:00 0 S
1751 Rule Winn 1918 only - Apr 14 2:00 1:00 D
1752 Rule Winn 1918 only - Oct 27 2:00 0 S
1753 Rule Winn 1937 only - May 16 2:00 1:00 D
1754 Rule Winn 1937 only - Sep 26 2:00 0 S
1755 Rule Winn 1942 only - Feb 9 2:00 1:00 W # War
1756 Rule Winn 1945 only - Aug 14 23:00u 1:00 P # Peace
1757 Rule Winn 1945 only - Sep lastSun 2:00 0 S
1758 Rule Winn 1946 only - May 12 2:00 1:00 D
1759 Rule Winn 1946 only - Oct 13 2:00 0 S
1760 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
1761 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
1762 Rule Winn 1950 only - May 1 2:00 1:00 D
1763 Rule Winn 1950 only - Sep 30 2:00 0 S
1764 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
1765 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
1766 Rule Winn 1959 only - Oct lastSun 2:00 0 S
1767 Rule Winn 1960 only - Sep lastSun 2:00 0 S
1768 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
1769 Rule Winn 1963 only - Sep 22 2:00 0 S
1770 Rule Winn 1966 1986 - Apr lastSun 2:00s 1:00 D
1771 Rule Winn 1966 2005 - Oct lastSun 2:00s 0 S
1772 Rule Winn 1987 2005 - Apr Sun>=1 2:00s 1:00 D
1773 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1774 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
1775 -6:00 Winn C%sT 2006
1781 # From Mark Brader (2003-07-26):
1782 # The first actual adoption of DST in Canada was at the municipal
1783 # level. As the [Toronto] Star put it (1912-06-07), "While people
1784 # elsewhere have long been talking of legislation to save daylight,
1785 # the city of Moose Jaw [Saskatchewan] has acted on its own hook."
1786 # DST in Moose Jaw began on Saturday, 1912-06-01 (no time mentioned:
1787 # presumably late evening, as below), and would run until "the end of
1788 # the summer". The discrepancy between municipal time and railroad
1791 # From Paul Eggert (2003-07-27):
1792 # Willett (1914-03) notes that DST "has been in operation ... in the
1793 # City of Moose Jaw, Saskatchewan, for one year."
1795 # From Paul Eggert (2019-07-25):
1796 # Pearce's book says Regina observed DST in 1914-1917. No dates and times,
1797 # unfortunately. It also says that in 1914 Saskatoon observed DST
1798 # from 1 June to 6 July, and that DST was also tried out in Davidson,
1799 # Melfort, and Prince Albert.
1801 # From Paul Eggert (2006-03-22):
1802 # Shanks & Pottenger say that since 1970 this region has mostly been as Regina.
1803 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
1804 # Other western towns (e.g. Lloydminster) are like Edmonton.
1805 # Matthews and Vincent (1998) write that Denare Beach and Creighton
1806 # are like Winnipeg, in violation of Saskatchewan law.
1808 # From W. Jones (1992-11-06):
1809 # The. . .below is based on information I got from our law library, the
1810 # provincial archives, and the provincial Community Services department.
1811 # A precise history would require digging through newspaper archives, and
1812 # since you didn't say what you wanted, I didn't bother.
1814 # Saskatchewan is split by a time zone meridian (105W) and over the years
1815 # the boundary became pretty ragged as communities near it reevaluated
1816 # their affiliations in one direction or the other. In 1965 a provincial
1817 # referendum favoured legislating common time practices.
1819 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
1820 # Saskatchewan 1978) was proclaimed, and established that the eastern
1821 # part of Saskatchewan would use CST year round, that districts in
1822 # northwest Saskatchewan would by default follow CST but could opt to
1823 # follow Mountain Time rules (thus 1 hour difference in the winter and
1824 # zero in the summer), and that districts in southwest Saskatchewan would
1825 # by default follow MT but could opt to follow CST.
1827 # It took a few years for the dust to settle (I know one story of a town
1828 # on one time zone having its school in another, such that a mom had to
1829 # serve her family lunch in two shifts), but presently it seems that only
1830 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
1831 # rules any more; all other districts appear to have used CST year round
1832 # since sometime in the 1960s.
1834 # From Chris Walton (2006-06-26):
1835 # The Saskatchewan time act which was last updated in 1996 is about 30 pages
1836 # long and rather painful to read.
1837 # http://www.qp.gov.sk.ca/documents/English/Statutes/Statutes/T14.pdf
1839 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1840 Rule Regina 1918 only - Apr 14 2:00 1:00 D
1841 Rule Regina 1918 only - Oct 27 2:00 0 S
1842 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
1843 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
1844 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
1845 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
1846 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
1847 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
1848 Rule Regina 1942 only - Feb 9 2:00 1:00 W # War
1849 Rule Regina 1945 only - Aug 14 23:00u 1:00 P # Peace
1850 Rule Regina 1945 only - Sep lastSun 2:00 0 S
1851 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
1852 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
1853 Rule Regina 1947 1957 - Apr lastSun 2:00 1:00 D
1854 Rule Regina 1947 1957 - Sep lastSun 2:00 0 S
1855 Rule Regina 1959 only - Apr lastSun 2:00 1:00 D
1856 Rule Regina 1959 only - Oct lastSun 2:00 0 S
1858 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
1859 Rule Swift 1957 only - Oct lastSun 2:00 0 S
1860 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
1861 Rule Swift 1959 only - Oct lastSun 2:00 0 S
1862 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
1863 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1864 Zone America/Regina -6:58:36 - LMT 1905 Sep
1865 -7:00 Regina M%sT 1960 Apr lastSun 2:00
1867 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
1868 -7:00 Canada M%sT 1946 Apr lastSun 2:00
1869 -7:00 Regina M%sT 1950
1870 -7:00 Swift M%sT 1972 Apr lastSun 2:00
1876 # From Alois Treindl (2019-07-19):
1877 # There was no DST in Alberta in 1967... Calgary Herald, 29 April 1967.
1878 # 1969, no DST, from Edmonton Journal 18 April 1969
1880 # From Paul Eggert (2019-07-25):
1881 # Pearce's book says that Alberta's 1948 Daylight Saving Act required
1882 # Mountain Standard Time without DST, and that "anyone who broke that law
1883 # could be fined up to $25 and costs". There seems to be no record of
1884 # anybody paying the fine. The law was not changed until an August 1971
1885 # plebiscite reinstituted DST in 1972. This story is also mentioned in:
1886 # Boyer JP. Forcing Choice: The Risky Reward of Referendums. Dundum. 2017.
1887 # ISBN 978-1459739123.
1889 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1890 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
1891 Rule Edm 1918 only - Oct 27 2:00 0 S
1892 Rule Edm 1919 only - May 27 2:00 0 S
1893 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
1894 Rule Edm 1920 only - Oct lastSun 2:00 0 S
1895 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
1896 Rule Edm 1942 only - Feb 9 2:00 1:00 W # War
1897 Rule Edm 1945 only - Aug 14 23:00u 1:00 P # Peace
1898 Rule Edm 1945 only - Sep lastSun 2:00 0 S
1899 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
1900 Rule Edm 1947 only - Sep lastSun 2:00 0 S
1901 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
1902 Rule Edm 1972 2006 - Oct lastSun 2:00 0 S
1903 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1904 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
1911 # From Paul Eggert (2006-03-22):
1912 # Shanks & Pottenger write that since 1970 most of this region has
1913 # been like Vancouver.
1914 # Dawson Creek uses MST. Much of east BC is like Edmonton.
1916 # From Matt Johnson (2015-09-21):
1917 # Fort Nelson, BC, Canada will cancel DST this year. So while previously they
1918 # were aligned with America/Vancouver, they're now aligned with
1919 # America/Dawson_Creek.
1920 # http://www.northernrockies.ca/EN/meta/news/archives/2015/northern-rockies-time-change.html
1922 # From Tim Parenti (2015-09-23):
1923 # This requires a new zone for the Northern Rockies Regional Municipality,
1924 # America/Fort_Nelson. The resolution of 2014-12-08 was reached following a
1925 # 2014-11-15 poll with nearly 75% support. Effectively, the municipality has
1926 # been on MST (-0700) like Dawson Creek since it advanced its clocks on
1929 # From Paul Eggert (2019-07-25):
1930 # Shanks says Fort Nelson did not observe DST in 1946, unlike Vancouver.
1931 # Alois Treindl confirmed this on 07-22, citing the 1946-04-27 Vancouver Daily
1932 # Province. He also cited the 1946-09-28 Victoria Daily Times, which said
1933 # that Vancouver, Victoria, etc. "change at midnight Saturday"; for now,
1934 # guess they meant 02:00 Sunday since 02:00 was common practice in Vancouver.
1936 # Early Vancouver, Volume Four, by Major J.S. Matthews, V.D., 2011 edition
1937 # says that a 1922 plebiscite adopted DST, but a 1923 plebiscite rejected it.
1938 # http://former.vancouver.ca/ctyclerk/archives/digitized/EarlyVan/SearchEarlyVan/Vol4pdf/MatthewsEarlyVancouverVol4_DaylightSavings.pdf
1939 # A catalog entry for a newspaper clipping seems to indicate that Vancouver
1940 # observed DST in 1941 from 07-07 through 09-27; see
1941 # https://searcharchives.vancouver.ca/daylight-saving-1918-starts-again-july-7-1941-start-d-s-sept-27-end-of-d-s-1941
1942 # We have no further details, so omit them for now.
1944 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
1945 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
1946 Rule Vanc 1918 only - Oct 27 2:00 0 S
1947 Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War
1948 Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace
1949 Rule Vanc 1945 only - Sep 30 2:00 0 S
1950 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
1951 Rule Vanc 1946 only - Sep 29 2:00 0 S
1952 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
1953 Rule Vanc 1962 2006 - Oct lastSun 2:00 0 S
1954 # Zone NAME STDOFF RULES FORMAT [UNTIL]
1955 Zone America/Vancouver -8:12:28 - LMT 1884
1956 -8:00 Vanc P%sT 1987
1958 Zone America/Dawson_Creek -8:00:56 - LMT 1884
1959 -8:00 Canada P%sT 1947
1960 -8:00 Vanc P%sT 1972 Aug 30 2:00
1962 Zone America/Fort_Nelson -8:10:47 - LMT 1884
1963 -8:00 Vanc P%sT 1946
1965 -8:00 Vanc P%sT 1987
1966 -8:00 Canada P%sT 2015 Mar 8 2:00
1968 # For Creston see America/Phoenix.
1970 # Northwest Territories, Nunavut, Yukon
1972 # From Chris Walton (2022-11-06):
1973 # Whitehorse Star - Thursday April 22, 1965 - page 1
1974 # title: DST Starts Monday ...
1975 # https://www.newspapers.com/image/578587481/
1976 # The title of this first article is wrong and/or misleading.
1977 # Also, the start time shown in the article is vague; it simply says "after
1978 # midnight" when it probably should have stated 2:00a.m....
1980 # Whitehorse Star - Monday October 25, 1965 - page 15 ...
1981 # https://www.newspapers.com/image/578589147/
1982 # The 1965 Yukon Council minutes can be found here:
1983 # http://assets.yukonarchives.ca/PER_YG_06_1965_C20_S02_v1.pdf
1984 # ... I do not currently believe that NWT touched any of its clocks in 1965....
1986 # Whitehorse Star - Thursday Feb 24,1966 - page 2
1987 # title: It's Time for YDT ...
1988 # https://www.newspapers.com/image/578575979/ ...
1989 # America/Whitehorse as a permanent change from UTC-9(YST) to
1990 # UTC-8(PST) at 00:00 on Sunday February 27, 1966....
1992 # Whitehorse Star - Friday April 28,1972 - page 6
1993 # title: Daylight Saving Time for N.W.T....
1994 # https://www.newspapers.com/image/578701610/ ...
1995 # Nunavut and NWT zones ... DST starting in 1972.... Start and End ...
1996 # should be the same as the rest of Canada
1999 # From Paul Eggert (2022-11-06):
2000 # For now, assume Yukon's 1965-04-22 spring forward was 00:00 -> 02:00, as this
2001 # seems likely than 02:00 -> 04:00 and matches "after midnight".
2003 # From Paul Eggert (2006-03-22):
2004 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
2005 # Mathew Englander (1996-10-07) gives the following refs:
2006 # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
2007 # c. 7 defines Yukon standard time as UTC-9....
2008 # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1).
2009 # [https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-i-21/latest/rsc-1985-c-i-21.html]
2010 # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00.
2011 # * O.I.C. 1980/02 established DST.
2012 # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00.
2014 # From Brian Inglis (2015-04-14):
2016 # I tried to trace the history of Yukon time and found the following
2017 # regulations, giving the reference title and URL if found, regulation name,
2018 # and relevant quote if available. Each regulation specifically revokes its
2019 # predecessor. The final reference is to the current Interpretation Act
2020 # authorizing and resulting from these regulatory changes.
2022 # Only recent regulations were retrievable via Yukon government site search or
2023 # index, and only some via Canadian legal sources. Other sources used include
2024 # articles titled "Standard Time and Time Zones in Canada" from JRASC via ADS
2025 # Abstracts, cited by ADO for 1932 ..., and updated versions from 1958 and
2026 # 1970 quoted below; each article includes current extracts from provincial
2027 # and territorial ST and DST regulations at the end, summaries and details of
2028 # standard times and daylight saving time at many locations across Canada,
2029 # with time zone maps, tables and calculations for Canadian Sunrise, Sunset,
2030 # and LMST; they also cover many countries and global locations, with a chart
2031 # and table showing current Universal Time offsets, and may be useful as
2032 # another source of information for 1970 and earlier.
2034 # * Standard Time and Time Zones in Canada; Smith, C.C.; JRASC, Vol. 26,
2035 # pp.49-77; February 1932; SAO/NASA Astrophysics Data System (ADS)
2036 # http://adsabs.harvard.edu/abs/1932JRASC..26...49S from p.75:
2037 # Yukon Interpretation Ordinance
2038 # Yukon standard time is the local mean time at the one hundred and
2039 # thirty-fifth meridian.
2041 # * Standard Time and Time Zones in Canada; Smith, C.C.; Thomson, Malcolm M.;
2042 # JRASC, Vol. 52, pp.193-223; October 1958; SAO/NASA Astrophysics Data System
2043 # (ADS) http://adsabs.harvard.edu/abs/1958JRASC..52..193S from pp.220-1:
2044 # Yukon Interpretation Ordinance, 1955, Chap. 16.
2046 # (1) Subject to this section, standard time shall be reckoned as nine
2047 # hours behind Greenwich Time and called Yukon Standard Time.
2049 # (2) Notwithstanding subsection (1), the Commissioner may make regulations
2050 # varying the manner of reckoning standard time.
2052 # * Yukon Territory Commissioner's Order 1966-20 Interpretation Ordinance
2053 # [no online source found]
2055 # * Standard Time and Time Zones in Canada; Thomson, Malcolm M.; JRASC,
2056 # Vol. 64, pp.129-162; June 1970; SAO/NASA Astrophysics Data System (ADS)
2057 # http://adsabs.harvard.edu/abs/1970JRASC..64..129T from p.156: Yukon
2058 # Territory Commissioner's Order 1967-59 Interpretation Ordinance ...
2060 # 1. Commissioner's Order 1966-20 dated at Whitehorse in the Yukon
2061 # Territory on 27th January, 1966, is hereby revoked.
2063 # 2. Yukon (East) Standard Time as defined by section 36 of the
2064 # Interpretation Ordinance from and after mid-night on the 28th day of May,
2065 # 1967 shall be reckoned in the same manner as Pacific Standard Time, that
2066 # is to say, eight hours behind Greenwich Time in the area of the Yukon
2067 # Territory lying east of the 138th degree longitude west.
2069 # 3. In the remainder of the Territory, lying west of the 138th degree
2070 # longitude west, Yukon (West) Standard Time shall be reckoned as nine
2071 # hours behind Greenwich Time.
2073 # * Yukon Standard Time defined as Pacific Standard Time, YCO 1973/214
2074 # https://www.canlii.org/en/yk/laws/regu/yco-1973-214/latest/yco-1973-214.html
2075 # C.O. 1973/214 INTERPRETATION ACT ...
2077 # 1. Effective October 28, 1973 Commissioner's Order 1967/59 is hereby
2080 # 2. Yukon Standard Time as defined by section 36 of the Interpretation
2081 # Act from and after midnight on the twenty-eighth day of October, 1973
2082 # shall be reckoned in the same manner as Pacific Standard Time, that is
2083 # to say eight hours behind Greenwich Time.
2085 # * O.I.C. 1980/02 INTERPRETATION ACT
2086 # https://mm.icann.org/pipermail/tz/attachments/20201125/d5adc93b/CAYTOIC1980-02DST1980-01-04-0001.pdf
2088 # * Yukon Daylight Saving Time, YOIC 1987/56
2089 # https://www.canlii.org/en/yk/laws/regu/yoic-1987-56/latest/yoic-1987-56.html
2090 # O.I.C. 1987/056 INTERPRETATION ACT ...
2092 # In every year between
2093 # (a) two o'clock in the morning in the first Sunday in April, and
2094 # (b) two o'clock in the morning in the last Sunday in October,
2095 # Standard Time shall be reckoned as seven hours behind Greenwich Time and
2096 # called Yukon Daylight Saving Time.
2098 # Dated ... 9th day of March, A.D., 1987.
2100 # * Yukon Daylight Saving Time 2006, YOIC 2006/127
2101 # https://www.canlii.org/en/yk/laws/regu/yoic-2006-127/latest/yoic-2006-127.html
2102 # O.I.C. 2006/127 INTERPRETATION ACT ...
2104 # 1. In Yukon each year the time for general purposes shall be 7 hours
2105 # behind Greenwich mean time during the period commencing at two o'clock
2106 # in the forenoon on the second Sunday of March and ending at two o'clock
2107 # in the forenoon on the first Sunday of November and shall be called
2108 # Yukon Daylight Saving Time.
2110 # 2. Order-in-Council 1987/56 is revoked.
2112 # 3. This order comes into force January 1, 2007.
2114 # * Interpretation Act, RSY 2002, c 125
2115 # https://www.canlii.org/en/yk/laws/stat/rsy-2002-c-125/latest/rsy-2002-c-125.html
2117 # From Chris Walton (2022-11-06):
2118 # The 5th edition of the Atlas of Canada contains a time zone map that
2119 # shows both legislated and observed time zone boundaries.
2120 # All communities on Baffin Island are shown to be observing Eastern time.
2121 # The date on the map is 1984.
2122 # https://ftp.maps.canada.ca/pub/nrcan_rncan/raster/atlas_5_ed/eng/other/referencemaps/mcr4056.pdf
2124 # From Rives McDow (1999-09-04):
2125 # Nunavut ... moved ... to incorporate the whole territory into one time zone.
2126 # Nunavut moves to single time zone Oct. 31
2127 # http://www.nunatsiaq.com/nunavut/nvt90903_13.html
2129 # From Antoine Leca (1999-09-06):
2130 # We then need to create a new timezone for the Kitikmeot region of Nunavut
2131 # to differentiate it from the Yellowknife region.
2133 # From Paul Eggert (1999-09-20):
2134 # Basic Facts: The New Territory
2135 # http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html
2136 # (1999) reports that ... Coral Harbour does not observe DST.
2138 # From Paul Eggert (2000-10-02):
2139 # Matthews and Vincent (1998) say the following, but we lack histories
2140 # for these potential new Zones.
2142 # The Canadian Forces station at Alert uses Eastern Time while the
2143 # handful of residents at the Eureka weather station [in the Central
2144 # zone] skip daylight savings. Baffin Island, which is crossed by the
2145 # Central, Eastern and Atlantic Time zones only uses Eastern Time.
2146 # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of
2147 # Central Time and Southampton Island [in the Central zone] is not
2148 # required to use daylight savings.
2150 # From <http://www.nunatsiaqonline.ca/archives/nunavut001130/nvt21110_02.html>
2151 # Nunavut now has two time zones (2000-11-10):
2152 # The Nunavut government would allow its employees in Kugluktuk and
2153 # Cambridge Bay to operate on central time year-round, putting them
2154 # one hour behind the rest of Nunavut for six months during the winter.
2155 # At the end of October the two communities had rebelled against
2156 # Nunavut's unified time zone, refusing to shift to eastern time with
2157 # the rest of the territory for the winter. Cambridge Bay remained on
2158 # central time, while Kugluktuk, even farther west, reverted to
2159 # mountain time, which they had used before the advent of Nunavut's
2160 # unified time zone in 1999.
2162 # From Rives McDow (2001-01-20), quoting the Nunavut government:
2163 # The preceding decision came into effect at midnight, Saturday Nov 4, 2000.
2165 # From Paul Eggert (2000-12-04):
2166 # Let's just keep track of the official times for now.
2168 # From Rives McDow (2001-03-07):
2169 # The premier of Nunavut has issued a ministerial statement advising
2170 # that effective 2001-04-01, the territory of Nunavut will revert
2171 # back to three time zones (mountain, central, and eastern). Of the
2172 # cities in Nunavut, Coral Harbor is the only one that I know of that
2173 # has said it will not observe dst, staying on EST year round. I'm
2174 # checking for more info, and will get back to you if I come up with
2176 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
2178 # From Gwillim Law (2005-05-21):
2180 # http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
2181 # (from a 1998 Canadian Geographic article), the de facto and de jure time
2182 # for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year
2183 # round. Using Google, it's easy to find other websites that confirm this.
2184 # I wasn't able to find how far back this time regimen goes, but since it
2185 # predates the creation of Nunavut, it probably goes back many years....
2186 # The Inuktitut name of Coral Harbour is Sallit, but it's rarely used.
2188 # From Paul Eggert (2014-10-17):
2189 # For lack of better information, assume that Southampton Island observed
2190 # daylight saving only during wartime. Gwillim Law's email also
2191 # mentioned maps now maintained by National Research Council Canada;
2192 # see above for an up-to-date link.
2194 # From Chris Walton (2007-03-01):
2195 # ... the community of Resolute (located on Cornwallis Island in
2196 # Nunavut) moved from Central Time to Eastern Time last November.
2197 # Basically the community did not change its clocks at the end of
2198 # daylight saving....
2199 # http://www.nnsl.com/frames/newspapers/2006-11/nov13_06none.html
2201 # From Chris Walton (2011-03-21):
2202 # Back in 2007 I initiated the creation of a new "zone file" for Resolute
2203 # Bay. Resolute Bay is a small community located about 900km north of
2204 # the Arctic Circle. The zone file was required because Resolute Bay had
2205 # decided to use UTC-5 instead of UTC-6 for the winter of 2006-2007.
2207 # According to new information which I received last week, Resolute Bay
2208 # went back to using UTC-6 in the winter of 2007-2008...
2210 # On March 11/2007 most of Canada went onto daylight saving. On March
2211 # 14/2007 I phoned the Resolute Bay hamlet office to do a "time check." I
2212 # talked to somebody that was both knowledgeable and helpful. I was able
2213 # to confirm that Resolute Bay was still operating on UTC-5. It was
2214 # explained to me that Resolute Bay had been on the Eastern Time zone
2215 # (EST) in the winter, and was now back on the Central Time zone (CDT).
2216 # i.e. the time zone had changed twice in the last year but the clocks
2217 # had not moved. The residents had to know which time zone they were in
2218 # so they could follow the correct TV schedule...
2220 # On Nov 02/2008 most of Canada went onto standard time. On Nov 03/2008 I
2221 # phoned the Resolute Bay hamlet office...[D]ue to the challenging nature
2222 # of the phone call, I decided to seek out an alternate source of
2223 # information. I found an e-mail address for somebody by the name of
2224 # Stephanie Adams whose job was listed as "Inns North Support Officer for
2225 # Arctic Co-operatives." I was under the impression that Stephanie lived
2226 # and worked in Resolute Bay...
2228 # On March 14/2011 I phoned the hamlet office again. I was told that
2229 # Resolute Bay had been using Central Standard Time over the winter of
2230 # 2010-2011 and that the clocks had therefore been moved one hour ahead
2231 # on March 13/2011. The person I talked to was aware that Resolute Bay
2232 # had previously experimented with Eastern Standard Time but he could not
2233 # tell me when the practice had stopped.
2235 # On March 17/2011 I searched the Web to find an e-mail address of
2236 # somebody that might be able to tell me exactly when Resolute Bay went
2237 # off Eastern Standard Time. I stumbled on the name "Aziz Kheraj." Aziz
2238 # used to be the mayor of Resolute Bay and he apparently owns half the
2239 # businesses including "South Camp Inn." This website has some info on
2241 # http://www.uphere.ca/node/493
2243 # I sent Aziz an e-mail asking when Resolute Bay had stopped using
2244 # Eastern Standard Time.
2246 # Aziz responded quickly with this: "hi, The time was not changed for the
2247 # 1 year only, the following year, the community went back to the old way
2248 # of "spring ahead-fall behind" currently we are zulu plus 5 hrs and in
2249 # the winter Zulu plus 6 hrs"
2251 # This of course conflicted with everything I had ascertained in November 2008.
2253 # I sent Aziz a copy of my 2008 e-mail exchange with Stephanie. Aziz
2254 # responded with this: "Hi, Stephanie lives in Winnipeg. I live here, You
2255 # may want to check with the weather office in Resolute Bay or do a
2256 # search on the weather through Env. Canada. web site"
2258 # If I had realized the Stephanie did not live in Resolute Bay I would
2259 # never have contacted her. I now believe that all the information I
2260 # obtained in November 2008 should be ignored...
2261 # I apologize for reporting incorrect information in 2008.
2263 # From Tim Parenti (2020-03-05):
2264 # The government of Yukon announced [yesterday] the cessation of seasonal time
2265 # changes. "After clocks are pushed ahead one hour on March 8, the territory
2266 # will remain on [UTC-07]. ... [The government] found 93 per cent of
2267 # respondents wanted to end seasonal time changes and, of that group, 70 per
2268 # cent wanted 'permanent Pacific Daylight Saving Time.'"
2269 # https://www.cbc.ca/news/canada/north/yukon-end-daylight-saving-time-1.5486358
2271 # Although the government press release prefers PDT, we prefer MST for
2272 # consistency with nearby Dawson Creek, Creston, and Fort Nelson.
2273 # https://yukon.ca/en/news/yukon-end-seasonal-time-change
2275 # From Andrew G. Smith (2020-09-24):
2276 # Yukon has completed its regulatory change to be on UTC -7 year-round....
2277 # http://www.gov.yk.ca/legislation/regs/oic2020_125.pdf
2278 # What we have done is re-defined Yukon Standard Time, as we are
2279 # authorized to do under section 33 of our Interpretation Act:
2280 # http://www.gov.yk.ca/legislation/acts/interpretation_c.pdf
2282 # From Paul Eggert (2020-09-24):
2283 # tzdb uses the obsolete YST abbreviation for standard time in Yukon through
2284 # about 1970, and uses PST for standard time in Yukon since then. Consistent
2285 # with that, use MST for -07, the new standard time in Yukon effective Nov. 1.
2287 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2288 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
2289 Rule NT_YK 1918 only - Oct 27 2:00 0 S
2290 Rule NT_YK 1919 only - May 25 2:00 1:00 D
2291 Rule NT_YK 1919 only - Nov 1 0:00 0 S
2292 Rule NT_YK 1942 only - Feb 9 2:00 1:00 W # War
2293 Rule NT_YK 1945 only - Aug 14 23:00u 1:00 P # Peace
2294 Rule NT_YK 1945 only - Sep 30 2:00 0 S
2295 Rule NT_YK 1972 1986 - Apr lastSun 2:00 1:00 D
2296 Rule NT_YK 1972 2006 - Oct lastSun 2:00 0 S
2297 Rule NT_YK 1987 2006 - Apr Sun>=1 2:00 1:00 D
2298 Rule Yukon 1965 only - Apr lastSun 0:00 2:00 DD
2299 Rule Yukon 1965 only - Oct lastSun 2:00 0 S
2300 # Zone NAME STDOFF RULES FORMAT [UNTIL]
2301 # formerly Frobisher Bay
2302 Zone America/Iqaluit 0 - -00 1942 Aug # Frobisher Bay est.
2303 -5:00 NT_YK E%sT 1999 Oct 31 2:00
2304 -6:00 Canada C%sT 2000 Oct 29 2:00
2307 Zone America/Resolute 0 - -00 1947 Aug 31 # Resolute founded
2308 -6:00 NT_YK C%sT 2000 Oct 29 2:00
2309 -5:00 - EST 2001 Apr 1 3:00
2310 -6:00 Canada C%sT 2006 Oct 29 2:00
2311 -5:00 - EST 2007 Mar 11 3:00
2314 Zone America/Rankin_Inlet 0 - -00 1957 # Rankin Inlet founded
2315 -6:00 NT_YK C%sT 2000 Oct 29 2:00
2316 -5:00 - EST 2001 Apr 1 3:00
2318 # aka Iqaluktuuttiaq
2319 Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.?
2320 -7:00 NT_YK M%sT 1999 Oct 31 2:00
2321 -6:00 Canada C%sT 2000 Oct 29 2:00
2322 -5:00 - EST 2000 Nov 5 0:00
2323 -6:00 - CST 2001 Apr 1 3:00
2325 Zone America/Yellowknife 0 - -00 1935 # Yellowknife founded?
2326 -7:00 NT_YK M%sT 1980
2328 Zone America/Inuvik 0 - -00 1953 # Inuvik founded
2329 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
2330 -7:00 NT_YK M%sT 1980
2332 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
2333 -9:00 NT_YK Y%sT 1965
2334 -9:00 Yukon Y%sT 1966 Feb 27 0:00
2336 -8:00 Canada P%sT 2020 Nov 1
2338 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
2339 -9:00 NT_YK Y%sT 1965
2340 -9:00 Yukon Y%sT 1973 Oct 28 0:00
2342 -8:00 Canada P%sT 2020 Nov 1
2346 ###############################################################################
2350 # From Paul Eggert (2014-12-07):
2351 # The Investigation and Analysis Service of the
2352 # Mexican Library of Congress (MLoC) has published a
2353 # history of Mexican local time (in Spanish)
2354 # http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm
2356 # Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC.
2357 # (In all cases we go with the MLoC.)
2358 # S&P report that Baja was at -8:00 in 1922/1923.
2359 # S&P say the 1930 transition in Baja was 1930-11-16.
2360 # S&P report no DST during summer 1931.
2361 # S&P report a transition at 1932-03-30 23:00, not 1932-04-01.
2363 # From Gwillim Law (2001-02-20):
2364 # There are some other discrepancies between the Decrees page and the
2365 # tz database. I think they can best be explained by supposing that
2366 # the researchers who prepared the Decrees page failed to find some of
2367 # the relevant documents.
2369 # From Alan Perry (1996-02-15):
2370 # A guy from our Mexico subsidiary finally found the Presidential Decree
2371 # outlining the timezone changes in Mexico.
2373 # ------------- Begin Forwarded Message -------------
2375 # I finally got my hands on the Official Presidential Decree that sets up the
2376 # rules for the DST changes. The rules are:
2378 # 1. The country is divided in 3 timezones:
2379 # - Baja California Norte (the Mexico/BajaNorte TZ)
2380 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
2381 # - The rest of the country (the Mexico/General TZ)
2383 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
2384 # at 2:00 AM, the times in each zone are as follows:
2389 # 3. The rest of the year, the times are as follows:
2394 # The Decree was published in Mexico's Official Newspaper on January 4th.
2396 # -------------- End Forwarded Message --------------
2397 # From Paul Eggert (1996-06-12):
2398 # For an English translation of the decree, see
2399 # "Diario Oficial: Time Zone Changeover" (1996-01-04).
2400 # http://mexico-travel.com/extra/timezone_eng.html
2402 # From Rives McDow (1998-10-08):
2403 # The State of Quintana Roo has reverted back to central STD and DST times
2404 # (i.e. UTC -0600 and -0500 as of 1998-08-02).
2406 # From Rives McDow (2000-01-10):
2407 # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time
2408 # zone 5 hours from the International Date Line, and will not observe daylight
2409 # savings time so as to stay on the same time zone as the southern part of
2410 # Arizona year round.
2412 # From Jesper Nørgaard, translating
2413 # <http://www.reforma.com/nacional/articulo/064327/> (2001-01-17):
2414 # In Oaxaca, the 55.000 teachers from the Section 22 of the National
2415 # Syndicate of Education Workers, refuse to apply daylight saving each
2416 # year, so that the more than 10,000 schools work at normal hour the
2419 # From Gwillim Law (2001-01-19):
2420 # <http://www.reforma.com/negocios_y_dinero/articulo/064481/> ... says
2422 # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced
2423 # that Summer Time will be reduced from seven to five months, starting
2425 # http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001
2426 # [translated], says "summer time will ... take effect on the first Sunday
2427 # in May, and end on the last Sunday of September.
2429 # From Arthur David Olson (2001-01-25):
2430 # The 2001-01-24 traditional Washington Post contained the page one
2431 # story "Timely Issue Divides Mexicans."...
2432 # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html
2433 # ... Mexico City Mayor López Obrador "...is threatening to keep
2434 # Mexico City and its 20 million residents on a different time than
2435 # the rest of the country..." In particular, López Obrador would abolish
2436 # observation of Daylight Saving Time.
2438 # Official statute published by the Energy Department
2439 # http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre
2440 # (2001-02-01) shows Baja and Chihauhua as still using US DST rules,
2441 # and Sonora with no DST. This was reported by Jesper Nørgaard (2001-02-03).
2443 # From Paul Eggert (2001-03-03):
2445 # https://www.latimes.com/archives/la-xpm-2001-mar-03-mn-32561-story.html
2446 # James F. Smith writes in today's LA Times
2447 # * Sonora will continue to observe standard time.
2448 # * Last week Mexico City's mayor Andrés Manuel López Obrador decreed that
2449 # the Federal District will not adopt DST.
2450 # * 4 of 16 district leaders announced they'll ignore the decree.
2451 # * The decree does not affect federal-controlled facilities including
2452 # the airport, banks, hospitals, and schools.
2454 # For now we'll assume that the Federal District will bow to federal rules.
2456 # From Jesper Nørgaard (2001-04-01):
2457 # I found some references to the Mexican application of daylight
2458 # saving, which modifies what I had already sent you, stating earlier
2459 # that a number of northern Mexican states would go on daylight
2460 # saving. The modification reverts this to only cover Baja California
2461 # (Norte), while all other states (except Sonora, who has no daylight
2462 # saving all year) will follow the original decree of president
2463 # Vicente Fox, starting daylight saving May 6, 2001 and ending
2464 # September 30, 2001.
2465 # References: "Diario de Monterrey" <http://www.diariodemonterrey.com/index.asp>
2466 # Palabra <http://palabra.infosel.com/010331/primera/ppri3101.pdf> (2001-03-31)
2468 # From Reuters (2001-09-04):
2469 # Mexico's Supreme Court on Tuesday declared that daylight savings was
2470 # unconstitutional in Mexico City, creating the possibility the
2471 # capital will be in a different time zone from the rest of the nation
2472 # next year.... The Supreme Court's ruling takes effect at 2:00
2473 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to
2474 # standard time. "This is so residents of the Federal District are not
2475 # subject to unexpected time changes," a statement from the court said.
2477 # From Jesper Nørgaard Welen (2002-03-12):
2478 # ... consulting my local grocery store(!) and my coworkers, they all insisted
2479 # that a new decision had been made to reinstate US style DST in Mexico....
2480 # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20)
2481 # confirms this. Sonora as usual is the only state where DST is not applied.
2483 # From Steffen Thorsen (2009-12-28):
2485 # Steffen Thorsen wrote:
2486 # > Mexico's House of Representatives has approved a proposal for northern
2487 # > Mexico's border cities to share the same daylight saving schedule as
2488 # > the United States.
2489 # Now this has passed both the Congress and the Senate, so starting from
2490 # 2010, some border regions will be the same:
2491 # http://www.signonsandiego.com/news/2009/dec/28/clocks-will-match-both-sides-border/
2492 # http://www.elmananarey.com/diario/noticia/nacional/noticias/empatan_horario_de_frontera_con_eu/621939
2495 # Could not find the new law text, but the proposed law text changes are here:
2496 # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/20091210-V.pdf
2497 # (Gaceta Parlamentaria)
2499 # There is also a list of the votes here:
2500 # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/V2-101209.html
2503 # https://www.timeanddate.com/news/time/north-mexico-dst-change.html
2505 # From Arthur David Olson (2010-01-20):
2507 # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010
2508 # includes this text:
2509 # En los municipios fronterizos de Tijuana y Mexicali en Baja California;
2510 # Juárez y Ojinaga en Chihuahua; Acuña y Piedras Negras en Coahuila;
2511 # Anáhuac en Nuevo León; y Nuevo Laredo, Reynosa y Matamoros en
2512 # Tamaulipas, la aplicación de este horario estacional surtirá efecto
2513 # desde las dos horas del segundo domingo de marzo y concluirá a las dos
2514 # horas del primer domingo de noviembre.
2515 # En los municipios fronterizos que se encuentren ubicados en la franja
2516 # fronteriza norte en el territorio comprendido entre la línea
2517 # internacional y la línea paralela ubicada a una distancia de veinte
2518 # kilómetros, así como la Ciudad de Ensenada, Baja California, hacia el
2519 # interior del país, la aplicación de este horario estacional surtirá
2520 # efecto desde las dos horas del segundo domingo de marzo y concluirá a
2521 # las dos horas del primer domingo de noviembre.
2523 # From Steffen Thorsen (2014-12-08), translated by Gwillim Law:
2524 # The Mexican state of Quintana Roo will likely change to EST in 2015.
2526 # http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo
2527 # "With this change, the time conflict that has existed between the municipios
2528 # of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an
2529 # end. The latter declared itself in rebellion 15 years ago when a time change
2530 # was initiated in Mexico, and since then it has refused to change its time
2531 # zone along with the rest of the country."
2533 # From Steffen Thorsen (2015-01-14), translated by Gwillim Law:
2534 # http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html
2535 # "...the new time zone will come into effect at two o'clock on the first Sunday
2536 # of February, when we will have to advance the clock one hour from its current
2538 # Also, the new zone will not use DST.
2540 # From Carlos Raúl Perasso (2015-02-02):
2541 # The decree that modifies the Mexican Hour System Law has finally
2542 # been published at the Diario Oficial de la Federación
2543 # http://www.dof.gob.mx/nota_detalle.php?codigo=5380123&fecha=31/01/2015
2544 # It establishes 5 zones for Mexico:
2545 # 1- Zona Centro (Central Zone): Corresponds to longitude 90 W,
2546 # includes most of Mexico, excluding what's mentioned below.
2547 # 2- Zona Pacífico (Pacific Zone): Longitude 105 W, includes the
2548 # states of Baja California Sur; Chihuahua; Nayarit (excluding Bahía
2549 # de Banderas which lies in Central Zone); Sinaloa and Sonora.
2550 # 3- Zona Noroeste (Northwest Zone): Longitude 120 W, includes the
2551 # state of Baja California.
2552 # 4- Zona Sureste (Southeast Zone): Longitude 75 W, includes the state
2554 # 5- The islands, reefs and keys shall take their timezone from the
2555 # longitude they are located at.
2557 # From Paul Eggert (2022-10-28):
2558 # The new Mexican law was published today:
2559 # https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022
2560 # This abolishes DST except where US DST rules are observed,
2561 # and in addition changes all of Chihuahua to -06 with no DST.
2563 # From Heitor David Pinto (2022-11-28):
2564 # Now the northern municipalities want to have the same time zone as the
2565 # respective neighboring cities in the US, for example Juárez in UTC-7 with
2566 # DST, matching El Paso, and Ojinaga in UTC-6 with DST, matching Presidio....
2567 # the president authorized the publication of the decree for November 29,
2568 # so the time change would occur on November 30 at 0:00.
2569 # http://puentelibre.mx/noticia/ciudad_juarez_cambio_horario_noviembre_2022/
2571 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2572 Rule Mexico 1931 only - May 1 23:00 1:00 D
2573 Rule Mexico 1931 only - Oct 1 0:00 0 S
2574 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
2575 Rule Mexico 1939 only - Jun 25 0:00 0 S
2576 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
2577 Rule Mexico 1941 only - Apr 1 0:00 0 S
2578 Rule Mexico 1943 only - Dec 16 0:00 1:00 W # War
2579 Rule Mexico 1944 only - May 1 0:00 0 S
2580 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
2581 Rule Mexico 1950 only - Jul 30 0:00 0 S
2582 Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D
2583 Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S
2584 Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D
2585 Rule Mexico 2001 only - Sep lastSun 2:00 0 S
2586 Rule Mexico 2002 2022 - Apr Sun>=1 2:00 1:00 D
2587 Rule Mexico 2002 2022 - Oct lastSun 2:00 0 S
2588 # Zone NAME STDOFF RULES FORMAT [UNTIL]
2589 # Quintana Roo; represented by Cancún
2590 Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 6:00u
2591 -6:00 - CST 1981 Dec 23
2592 -5:00 Mexico E%sT 1998 Aug 2 2:00
2593 -6:00 Mexico C%sT 2015 Feb 1 2:00
2595 # Campeche, Yucatán; represented by Mérida
2596 Zone America/Merida -5:58:28 - LMT 1922 Jan 1 6:00u
2597 -6:00 - CST 1981 Dec 23
2598 -5:00 - EST 1982 Dec 2
2600 # Coahuila, Nuevo León, Tamaulipas (near US border)
2601 # This includes the following municipalities:
2602 # in Coahuila: Acuña, Allende, Guerrero, Hidalgo, Jiménez, Morelos, Nava,
2603 # Ocampo, Piedras Negras, Villa Unión, Zaragoza
2604 # in Nuevo León: Anáhuac
2605 # in Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo,
2606 # Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, Matamoros.
2607 # https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022
2608 Zone America/Matamoros -6:30:00 - LMT 1922 Jan 1 6:00u
2611 -6:00 Mexico C%sT 2010
2613 # Durango; Coahuila, Nuevo León, Tamaulipas (away from US border)
2614 Zone America/Monterrey -6:41:16 - LMT 1922 Jan 1 6:00u
2619 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 7:00u
2620 -7:00 - MST 1927 Jun 10 23:00
2621 -6:00 - CST 1930 Nov 15
2622 -7:00 Mexico M%sT 1932 Apr 1
2623 -6:00 Mexico C%sT 2001 Sep 30 2:00
2624 -6:00 - CST 2002 Feb 20
2626 # Chihuahua (near US border - western side)
2627 # This includes the municipalities of Janos, Ascensión, Juárez, Guadalupe,
2628 # and Práxedis G Guerrero.
2629 # http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf
2630 Zone America/Ciudad_Juarez -7:05:56 - LMT 1922 Jan 1 7:00u
2631 -7:00 - MST 1927 Jun 10 23:00
2632 -6:00 - CST 1930 Nov 15
2633 -7:00 Mexico M%sT 1932 Apr 1
2635 -6:00 Mexico C%sT 1998
2636 -6:00 - CST 1998 Apr Sun>=1 3:00
2637 -7:00 Mexico M%sT 2010
2638 -7:00 US M%sT 2022 Oct 30 2:00
2639 -6:00 - CST 2022 Nov 30 0:00
2641 # Chihuahua (near US border - eastern side)
2642 # The municipalities of Coyame del Sotol, Ojinaga, and Manuel Benavides.
2643 # http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf
2644 Zone America/Ojinaga -6:57:40 - LMT 1922 Jan 1 7:00u
2645 -7:00 - MST 1927 Jun 10 23:00
2646 -6:00 - CST 1930 Nov 15
2647 -7:00 Mexico M%sT 1932 Apr 1
2649 -6:00 Mexico C%sT 1998
2650 -6:00 - CST 1998 Apr Sun>=1 3:00
2651 -7:00 Mexico M%sT 2010
2652 -7:00 US M%sT 2022 Oct 30 2:00
2653 -6:00 - CST 2022 Nov 30 0:00
2655 # Chihuahua (away from US border)
2656 Zone America/Chihuahua -7:04:20 - LMT 1922 Jan 1 7:00u
2657 -7:00 - MST 1927 Jun 10 23:00
2658 -6:00 - CST 1930 Nov 15
2659 -7:00 Mexico M%sT 1932 Apr 1
2661 -6:00 Mexico C%sT 1998
2662 -6:00 - CST 1998 Apr Sun>=1 3:00
2663 -7:00 Mexico M%sT 2022 Oct 30 2:00
2666 Zone America/Hermosillo -7:23:52 - LMT 1922 Jan 1 7:00u
2667 -7:00 - MST 1927 Jun 10 23:00
2668 -6:00 - CST 1930 Nov 15
2669 -7:00 Mexico M%sT 1932 Apr 1
2670 -6:00 - CST 1942 Apr 24
2671 -7:00 - MST 1949 Jan 14
2673 -7:00 Mexico M%sT 1999
2676 # Baja California Sur, Nayarit (except Bahía de Banderas), Sinaloa
2677 Zone America/Mazatlan -7:05:40 - LMT 1922 Jan 1 7:00u
2678 -7:00 - MST 1927 Jun 10 23:00
2679 -6:00 - CST 1930 Nov 15
2680 -7:00 Mexico M%sT 1932 Apr 1
2681 -6:00 - CST 1942 Apr 24
2682 -7:00 - MST 1949 Jan 14
2688 # From Alexander Krivenyshev (2010-04-21):
2689 # According to news, Bahía de Banderas (Mexican state of Nayarit)
2690 # changed time zone UTC-7 to new time zone UTC-6 on April 4, 2010 (to
2691 # share the same time zone as nearby city Puerto Vallarta, Jalisco).
2694 # Bahía de Banderas homologa su horario al del centro del
2695 # país, a partir de este domingo
2696 # http://www.nayarit.gob.mx/notes.asp?id=20748
2698 # Bahía de Banderas homologa su horario con el del Centro del
2700 # http://www.bahiadebanderas.gob.mx/principal/index.php?option=com_content&view=article&id=261:bahia-de-banderas-homologa-su-horario-con-el-del-centro-del-pais&catid=42:comunicacion-social&Itemid=50
2703 # Puerto Vallarta and Bahía de Banderas: One Time Zone
2704 # http://virtualvallarta.com/puertovallarta/puertovallarta/localnews/2009-12-03-Puerto-Vallarta-and-Bahia-de-Banderas-One-Time-Zone.shtml
2705 # http://www.worldtimezone.com/dst_news/dst_news_mexico08.html
2707 # "Mexico's Senate approved the amendments to the Mexican Schedule System that
2708 # will allow Bahía de Banderas and Puerto Vallarta to share the same time
2710 # Baja California Sur, Nayarit, Sinaloa
2712 # From Arthur David Olson (2010-05-01):
2713 # Use "Bahia_Banderas" to keep the name to fourteen characters.
2715 Zone America/Bahia_Banderas -7:01:00 - LMT 1922 Jan 1 7:00u
2716 -7:00 - MST 1927 Jun 10 23:00
2717 -6:00 - CST 1930 Nov 15
2718 -7:00 Mexico M%sT 1932 Apr 1
2719 -6:00 - CST 1942 Apr 24
2720 -7:00 - MST 1949 Jan 14
2722 -7:00 Mexico M%sT 2010 Apr 4 2:00
2726 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 7:00u
2728 -8:00 - PST 1927 Jun 10 23:00
2729 -7:00 - MST 1930 Nov 15
2730 -8:00 - PST 1931 Apr 1
2731 -8:00 1:00 PDT 1931 Sep 30
2732 -8:00 - PST 1942 Apr 24
2733 -8:00 1:00 PWT 1945 Aug 14 23:00u
2734 -8:00 1:00 PPT 1945 Nov 12 # Peace
2735 -8:00 - PST 1948 Apr 5
2736 -8:00 1:00 PDT 1949 Jan 14
2741 -8:00 Mexico P%sT 2001
2742 -8:00 US P%sT 2002 Feb 20
2743 -8:00 Mexico P%sT 2010
2745 # From Paul Eggert (2006-03-22):
2746 # Formerly there was an America/Ensenada zone, which differed from
2747 # America/Tijuana only in that it did not observe DST from 1976
2748 # through 1995. This was as per Shanks (1999). But Shanks & Pottenger say
2749 # Ensenada did not observe DST from 1948 through 1975. Guy Harris reports
2750 # that the 1987 OAG says "Only Ensenada, Mexicali, San Felipe and
2751 # Tijuana observe DST," which agrees with Shanks & Pottenger but implies that
2752 # DST-observance was a town-by-town matter back then. This concerns
2753 # data after 1970 so most likely there should be at least one Zone
2754 # other than America/Tijuana for Baja, but it's not clear yet what its
2755 # name or contents should be.
2757 # From Paul Eggert (2015-10-08):
2758 # Formerly there was an America/Santa_Isabel zone, but this appears to
2759 # have come from a misreading of
2760 # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010
2761 # It has been moved to the 'backward' file.
2763 # From Paul Eggert (2022-10-28):
2764 # Today's new law states that the entire state of Baja California
2765 # follows US DST rules, which agrees with simplifications noted above.
2771 ###############################################################################
2775 # For 1899 Milne gives -3:58:29.2.
2777 # From P Chan (2020-12-09 and 2020-12-11):
2778 # Standard time of GMT-4 was adopted in 1911.
2779 # Definition of Time Act, 1911 (1911-7) [1911-08-28]
2780 # 1912, Laws of Barbados (5 v.), OCLC Number: 919801291, Vol. 4, Image No. 522
2781 # 1944, Laws of Barbados (5 v.), OCLC Number: 84548697, Vol. 4, Image No. 122
2782 # http://llmc.com/browse.aspx?type=2&coll=85&div=297
2784 # DST was observed in 1942-44.
2785 # Defence (Daylight Saving) Regulations, 1942, 1942-04-13
2786 # Defence (Daylight Saving) (Repeal) Regulations, 1942, 1942-08-22
2787 # Defence (Daylight Saving) Regulations, 1943, 1943-04-16
2788 # Defence (Daylight Saving) (Repeal) Regulations, 1943, 1943-09-01
2789 # Defence (Daylight Saving) Regulations, 1944, 1944-03-21
2790 # [Defence (Daylight Saving) (Amendment) Regulations 1944, 1944-03-28]
2791 # Defence (Daylight Saving) (Repeal) Regulations, 1944, 1944-08-30
2793 # 1914-, Subsidiary Legis., Annual Vols. OCLC Number: 226290591
2794 # 1942: Image Nos. 527-528, 555-556
2795 # 1943: Image Nos. 178-179, 198
2796 # 1944: Image Nos. 113-115, 129
2797 # http://llmc.com/titledescfull.aspx?type=2&coll=85&div=297&set=98437
2799 # From Tim Parenti (2021-02-20):
2800 # The transitions below are derived from P Chan's sources, except that the 1977
2801 # through 1980 transitions are from Shanks & Pottenger since we have no better
2802 # data there. Of particular note, the 1944 DST regulation only advanced the
2803 # time to "exactly three and a half hours later than Greenwich mean time", as
2804 # opposed to "three hours" in the 1942 and 1943 regulations.
2806 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2807 Rule Barb 1942 only - Apr 19 5:00u 1:00 D
2808 Rule Barb 1942 only - Aug 31 6:00u 0 S
2809 Rule Barb 1943 only - May 2 5:00u 1:00 D
2810 Rule Barb 1943 only - Sep 5 6:00u 0 S
2811 Rule Barb 1944 only - Apr 10 5:00u 0:30 -
2812 Rule Barb 1944 only - Sep 10 6:00u 0 S
2813 Rule Barb 1977 only - Jun 12 2:00 1:00 D
2814 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
2815 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
2816 Rule Barb 1979 only - Sep 30 2:00 0 S
2817 Rule Barb 1980 only - Sep 25 2:00 0 S
2818 # Zone NAME STDOFF RULES FORMAT [UNTIL]
2820 Zone America/Barbados -3:58:29 - LMT 1911 Aug 28 # Bridgetown
2821 -4:00 Barb A%sT 1944
2822 -4:00 Barb AST/-0330 1945
2827 # From P Chan (2020-11-03):
2828 # Below are some laws related to the time in British Honduras/Belize:
2830 # Definition of Time Ordinance, 1927 (No.4 of 1927) [1927-04-01]
2831 # Ordinances of British Honduras Passed in the Year 1927, p 19-20
2832 # https://books.google.com/books?id=LqEpAQAAMAAJ&pg=RA3-PA19
2834 # Definition of Time (Amendment) Ordinance, 1942 (No. 5 of 1942) [1942-06-27]
2835 # Ordinances of British Honduras Passed in the Year 1942, p 31-32
2836 # https://books.google.com/books?id=h6MpAQAAMAAJ&pg=RA6-PA95-IA44
2838 # Definition of Time Ordinance, 1945 (No. 19 of 1945) [1945-12-15]
2839 # Ordinances of British Honduras Passed in the Year 1945, p 49-50
2840 # https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA2-PP1
2842 # Definition of Time Ordinance, 1947 (No. 1 of 1947) [1947-03-11]
2843 # Ordinances of British Honduras Passed in the Year 1947, p 1-2
2844 # https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA3-PA1
2846 # Time (Definition of) Ordinance (Chapter 180)
2847 # The Laws of British Honduras in Force on the 15th Day of September, 1958 , Volume IV, p 2580
2848 # https://books.google.com/books?id=v5QpAQAAMAAJ&pg=PA2580
2850 # Time (Definition of) (Amendment) Ordinance, 1968 (No. 13 of 1968) [1968-08-03]
2851 # https://books.google.com/books?id=xij7KEB_58wC&pg=RA1-PA428-IA9
2853 # Definition of Time Act (Chapter 339)
2854 # Law of Belize, Revised Edition 2000
2855 # http://www.belizelaw.org/web/lawadmin/PDF%20files/cap339.pdf
2857 # From Paul Eggert (2020-11-03):
2858 # The transitions below are derived from P Chan's sources, except that the
2859 # 1973 through 1983 transitions are from Shanks & Pottenger since we have
2860 # no better data there.
2862 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2863 Rule Belize 1918 1941 - Oct Sat>=1 24:00 0:30 -0530
2864 Rule Belize 1919 1942 - Feb Sat>=8 24:00 0 CST
2865 Rule Belize 1942 only - Jun 27 24:00 1:00 CWT
2866 Rule Belize 1945 only - Aug 14 23:00u 1:00 CPT
2867 Rule Belize 1945 only - Dec 15 24:00 0 CST
2868 Rule Belize 1947 1967 - Oct Sat>=1 24:00 0:30 -0530
2869 Rule Belize 1948 1968 - Feb Sat>=8 24:00 0 CST
2870 Rule Belize 1973 only - Dec 5 0:00 1:00 CDT
2871 Rule Belize 1974 only - Feb 9 0:00 0 CST
2872 Rule Belize 1982 only - Dec 18 0:00 1:00 CDT
2873 Rule Belize 1983 only - Feb 12 0:00 0 CST
2874 # Zone NAME STDOFF RULES FORMAT [UNTIL]
2875 Zone America/Belize -5:52:48 - LMT 1912 Apr 1
2880 # From Paul Eggert (2022-07-27):
2881 # For 1899 Milne gives -4:19:18.3 as the meridian of the clock tower,
2882 # Bermuda dockyard, Ireland I. This agrees with standard offset given in the
2883 # Daylight Saving Act, 1917 cited below.
2884 # It is not known when this time became standard for Bermuda; guess 1890.
2885 # The transition to -04 was specified by:
2886 # 1930: The Time Zone Act, 1929 (1929: No. 39) [1929-11-08]
2887 # https://books.google.com/books?id=7tdMAQAAIAAJ&pg=RA54-PP1
2889 # From P Chan (2020-11-20):
2890 # Most of the information can be found online from the Bermuda National
2891 # Library - Digital Collection which includes The Royal Gazette (RG) until 1957
2892 # https://bnl.contentdm.oclc.org/digital/
2893 # I will cite the ID. For example, [10000] means
2894 # https://bnl.contentdm.oclc.org/digital/collection/BermudaNP02/id/10000
2896 # 1917: Apr 5 midnight to Sep 30 midnight
2897 # Daylight Saving Act, 1917 (1917 No. 13) [1917-04-02]
2898 # Bermuda Acts and Resolves 1917, p 37-38
2899 # https://books.google.com/books?id=M-lCAQAAMAAJ&pg=PA36-IA2
2900 # RG, 1917-04-04, p 6 [42340] gives the spring forward date.
2902 # 1918: Apr 13 midnight to Sep 15 midnight
2903 # Daylight Saving Act, 1918 (1918 No. 9) [1918-04-06]
2904 # Bermuda Acts and Resolves 1917, p 13
2905 # https://books.google.com/books?id=K-lCAQAAMAAJ&pg=RA1-PA7
2907 # Note that local mean time was still used before 1930.
2909 # During WWII, DST was introduced by Defence Regulations
2910 # 1942: Jan 11 02:00 to Oct 18 02:00 [113646], [115726]
2911 # 1943: Mar 21 02:00 to Oct 31 02:00 [116704], [118193]
2912 # 1944: Mar 12 02:00 to Nov 5 02:00 [119225], [121593]
2913 # 1945: Mar 11 02:00 to Nov 4 02:00 [122369], [124461]
2914 # RG, 1942-01-08, p 2, 1942-10-12, p 2 , 1943-03-06, p 2, 1943-09-03, p 1,
2915 # 1944-02-29, p 6, 1944-09-20, p 2, 1945-02-13, p 2, 1945-11-03, p 1
2917 # In 1946, the House of Assembly rejected DST twice. [128686], [128076]
2918 # RG, 1946-03-16 p 1,1946-04-13 p 1
2920 # 1947: third Sunday in May 02:00 to second Sunday in September 02:00
2921 # DST in 1947 was defined in the Daylight Saving Act, 1947 (1947: No. 12)
2922 # which expired at the end of the year. [125784] ,[132405], [144454], [138226]
2923 # RG, 1947-02-27, p 1, 1947-05-15, p 1, 1947-09-13, p 1, 1947-12-30, p 1
2925 # 1948-1952: fourth Sunday in May 02:00 to first Sunday in September 02:00
2926 # DST in 1948 was defined in the Daylight Saving Act, 1948 (1948 : No. 12)
2927 # which was set to expired at the end of the year but it was extended until
2928 # the end of 1952 and was not further extended.
2929 # [129802], [139403], [146008], [135240], [144330], [139049], [143309],
2930 # [148271], [149773], [153589], [153802], [155924]
2931 # RG, 1948-04-13, p 1, 1948-05-22, p 1, 1948-09-04, p 1, 1949-05-21, p1,
2932 # 1949-09-03, p 1, 1950-05-27 p 1, 1950-09-02, p 1, 1951-05-27, p 1,
2933 # 1951-09-01, p 1, 1952-05-23, p 1, 1952-09-26, p 1, 1952-12-21, p 8
2935 # In 1953-1955, the House of Assembly rejected DST each year. [158996],
2936 # [162620], [166720] RG, 1953-05-02, p 1, 1954-04-01 p 1, 1955-03-12, p 1
2938 # 1956: fourth Sunday in May 02:00 to last Sunday in October 02:00
2939 # Time Zone (Seasonal Variation) Act, 1956 (1956: No.44) [1956-05-25]
2940 # Bermuda Public Acts 1956, p 331-332
2941 # https://books.google.com/books?id=Xs1AlmD_cEwC&pg=PA63
2943 # The extension of the Act was rejected by the House of Assembly. [176218]
2944 # RG, 1956-12-13, p 1
2946 # From the Chronological Table of Public and Private Acts up to 1985, it seems
2947 # that there does not exist other Acts related to DST before 1973.
2948 # https://books.google.com/books?id=r9hMAQAAIAAJ&pg=RA23-PA1
2949 # Public Acts of the Legislature of the Islands of Bermuda, Together with
2950 # Statutory Instruments in Force Thereunder, Vol VII
2952 # From Dan Jones, reporting in The Royal Gazette (2006-06-26):
2953 # Next year, however, clocks in the US will go forward on the second Sunday
2954 # in March, until the first Sunday in November. And, after the Time Zone
2955 # (Seasonal Variation) Bill 2006 was passed in the House of Assembly on
2956 # Friday, the same thing will happen in Bermuda.
2957 # http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135
2959 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2960 Rule Bermuda 1917 only - Apr 5 24:00 1:00 -
2961 Rule Bermuda 1917 only - Sep 30 24:00 0 -
2962 Rule Bermuda 1918 only - Apr 13 24:00 1:00 -
2963 Rule Bermuda 1918 only - Sep 15 24:00 0 S
2964 Rule Bermuda 1942 only - Jan 11 2:00 1:00 D
2965 Rule Bermuda 1942 only - Oct 18 2:00 0 S
2966 Rule Bermuda 1943 only - Mar 21 2:00 1:00 D
2967 Rule Bermuda 1943 only - Oct 31 2:00 0 S
2968 Rule Bermuda 1944 1945 - Mar Sun>=8 2:00 1:00 D
2969 Rule Bermuda 1944 1945 - Nov Sun>=1 2:00 0 S
2970 Rule Bermuda 1947 only - May Sun>=15 2:00 1:00 D
2971 Rule Bermuda 1947 only - Sep Sun>=8 2:00 0 S
2972 Rule Bermuda 1948 1952 - May Sun>=22 2:00 1:00 D
2973 Rule Bermuda 1948 1952 - Sep Sun>=1 2:00 0 S
2974 Rule Bermuda 1956 only - May Sun>=22 2:00 1:00 D
2975 Rule Bermuda 1956 only - Oct lastSun 2:00 0 S
2977 # Zone NAME STDOFF RULES FORMAT [UNTIL]
2979 Zone Atlantic/Bermuda -4:19:18 - LMT 1890 # Hamilton
2980 -4:19:18 Bermuda BMT/BST 1930 Jan 1 2:00
2981 -4:00 Bermuda A%sT 1974 Apr 28 2:00
2982 -4:00 Canada A%sT 1976
2987 # Milne gives -5:36:13.3 as San José mean time.
2989 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
2990 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
2991 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
2992 Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D
2993 # IATA SSIM (1991-09) says the following was at 1:00;
2994 # go with Shanks & Pottenger.
2995 Rule CR 1991 only - Jul 1 0:00 0 S
2996 Rule CR 1992 only - Mar 15 0:00 0 S
2997 # There are too many San Josés elsewhere, so we'll use 'Costa Rica'.
2998 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3000 Zone America/Costa_Rica -5:36:13 - LMT 1890 # San José
3001 -5:36:13 - SJMT 1921 Jan 15 # San José Mean Time
3004 # no information; probably like America/Costa_Rica
3008 # From Paul Eggert (2013-02-21):
3009 # Milne gives -5:28:50.45 for the observatory at Havana, -5:29:23.57
3010 # for the port, and -5:30 for meteorological observations.
3011 # For now, stick with Shanks & Pottenger.
3013 # From Arthur David Olson (1999-03-29):
3014 # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between
3015 # the Cuban National Team and the Baltimore Orioles was carried live on
3016 # the Orioles Radio Network, including affiliate WTOP in Washington, DC.
3017 # During the game, play-by-play announcer Jim Hunter noted that
3018 # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving
3019 # Time today." (The "two hour" remark referred to losing one hour of
3020 # sleep on 1999-03-28 - when the announcers were in Cuba as it switched
3021 # to DST - and one more hour on 1999-04-04 - when the announcers will have
3022 # returned to Baltimore, which switches on that date.)
3024 # From Steffen Thorsen (2013-11-11):
3025 # DST start in Cuba in 2004 ... does not follow the same rules as the
3026 # years before. The correct date should be Sunday 2004-03-28 00:00 ...
3027 # https://web.archive.org/web/20040402060750/http://www.granma.cu/espanol/2004/marzo/sab27/reloj.html
3029 # From Evert van der Veer via Steffen Thorsen (2004-10-28):
3030 # Cuba is not going back to standard time this year.
3031 # From Paul Eggert (2006-03-22):
3032 # http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html
3033 # says that it's due to a problem at the Antonio Guiteras
3034 # thermoelectric plant, and says "This October there will be no return
3035 # to normal hours (after daylight saving time)".
3036 # For now, let's assume that it's a temporary measure.
3038 # From Carlos A. Carnero Delgado (2005-11-12):
3039 # This year (just like in 2004-2005) there's no change in time zone
3040 # adjustment in Cuba. We will stay in daylight saving time:
3041 # http://www.granma.cu/espanol/2005/noviembre/mier9/horario.html
3043 # From Jesper Nørgaard Welen (2006-10-21):
3044 # An article in GRANMA INTERNACIONAL claims that Cuba will end
3045 # the 3 years of permanent DST next weekend, see
3046 # http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html
3047 # "On Saturday night, October 28 going into Sunday, October 29, at 01:00,
3048 # watches should be set back one hour - going back to 00:00 hours - returning
3049 # to the normal schedule....
3051 # From Paul Eggert (2007-03-02):
3052 # <http://www.granma.cubaweb.cu/english/news/art89.html>, dated yesterday,
3053 # says Cuban clocks will advance at midnight on March 10.
3054 # For lack of better information, assume Cuba will use US rules,
3055 # except that it switches at midnight standard time as usual.
3057 # From Steffen Thorsen (2007-10-25):
3058 # Carlos Alberto Fonseca Arauz informed me that Cuba will end DST one week
3059 # earlier - on the last Sunday of October, just like in 2006.
3061 # He supplied these references:
3063 # http://www.prensalatina.com.mx/article.asp?ID=%7B4CC32C1B-A9F7-42FB-8A07-8631AFC923AF%7D&language=ES
3064 # http://actualidad.terra.es/sociedad/articulo/cuba_llama_ahorrar_energia_cambio_1957044.htm
3066 # From Alex Krivenyshev (2007-10-25):
3067 # Here is also article from Granma (Cuba):
3069 # Regirá el Horario Normal desde el próximo domingo 28 de octubre
3070 # http://www.granma.cubaweb.cu/2007/10/24/nacional/artic07.html
3072 # http://www.worldtimezone.com/dst_news/dst_news_cuba03.html
3074 # From Arthur David Olson (2008-03-09):
3075 # I'm in Maryland which is now observing United States Eastern Daylight
3076 # Time. At 9:44 local time I used RealPlayer to listen to
3077 # http://media.enet.cu/radioreloj
3078 # a Cuban information station, and heard
3079 # the time announced as "ocho cuarenta y cuatro" ("eight forty-four"),
3080 # indicating that Cuba is still on standard time.
3082 # From Steffen Thorsen (2008-03-12):
3083 # It seems that Cuba will start DST on Sunday, 2007-03-16...
3084 # It was announced yesterday, according to this source (in Spanish):
3085 # http://www.nnc.cubaweb.cu/marzo-2008/cien-1-11-3-08.htm
3087 # Some more background information is posted here:
3088 # https://www.timeanddate.com/news/time/cuba-starts-dst-march-16.html
3090 # The article also says that Cuba has been observing DST since 1963,
3091 # while Shanks (and tzdata) has 1965 as the first date (except in the
3092 # 1940's). Many other web pages in Cuba also claim that it has been
3093 # observed since 1963, but with the exception of 1970 - an exception
3094 # which is not present in tzdata/Shanks. So there is a chance we need to
3095 # change some historic records as well.
3098 # http://www.radiohc.cu/espanol/noticias/mar07/11mar/hor.htm
3100 # From Jesper Nørgaard Welen (2008-03-13):
3101 # The Cuban time change has just been confirmed on the most authoritative
3102 # web site, the Granma. Please check out
3103 # http://www.granma.cubaweb.cu/2008/03/13/nacional/artic10.html
3105 # Basically as expected after Steffen Thorsen's information, the change
3106 # will take place midnight between Saturday and Sunday.
3108 # From Arthur David Olson (2008-03-12):
3109 # Assume Sun>=15 (third Sunday) going forward.
3111 # From Alexander Krivenyshev (2009-03-04)
3112 # According to the Radio Reloj - Cuba will start Daylight Saving Time on
3113 # midnight between Saturday, March 07, 2009 and Sunday, March 08, 2009-
3114 # not on midnight March 14 / March 15 as previously thought.
3116 # http://www.worldtimezone.com/dst_news/dst_news_cuba05.html
3119 # From Arthur David Olson (2009-03-09)
3120 # I listened over the Internet to
3121 # http://media.enet.cu/readioreloj
3122 # this morning; when it was 10:05 a. m. here in Bethesda, Maryland the
3123 # the time was announced as "diez cinco" - the same time as here, indicating
3124 # that has indeed switched to DST. Assume second Sunday from 2009 forward.
3126 # From Steffen Thorsen (2011-03-08):
3127 # Granma announced that Cuba is going to start DST on 2011-03-20 00:00:00
3128 # this year. Nothing about the end date known so far (if that has
3132 # http://granma.co.cu/2011/03/08/nacional/artic01.html
3135 # https://www.timeanddate.com/news/time/cuba-starts-dst-2011.html
3137 # From Steffen Thorsen (2011-10-30)
3138 # Cuba will end DST two weeks later this year. Instead of going back
3139 # tonight, it has been delayed to 2011-11-13 at 01:00.
3141 # One source (Spanish)
3142 # http://www.radioangulo.cu/noticias/cuba/17105-cuba-restablecera-el-horario-del-meridiano-de-greenwich.html
3145 # https://www.timeanddate.com/news/time/cuba-time-changes-2011.html
3147 # From Steffen Thorsen (2012-03-01)
3148 # According to Radio Reloj, Cuba will start DST on Midnight between March
3151 # Radio Reloj has the following info (Spanish):
3152 # http://www.radioreloj.cu/index.php/noticias-radio-reloj/71-miscelaneas/7529-cuba-aplicara-el-horario-de-verano-desde-el-1-de-abril
3155 # https://www.timeanddate.com/news/time/cuba-starts-dst-2012.html
3157 # From Steffen Thorsen (2012-11-03):
3158 # Radio Reloj and many other sources report that Cuba is changing back
3159 # to standard time on 2012-11-04:
3160 # http://www.radioreloj.cu/index.php/noticias-radio-reloj/36-nacionales/9961-regira-horario-normal-en-cuba-desde-el-domingo-cuatro-de-noviembre
3161 # From Paul Eggert (2012-11-03):
3162 # For now, assume the future rule is first Sunday in November.
3164 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3165 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
3166 Rule Cuba 1928 only - Oct 10 0:00 0 S
3167 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
3168 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
3169 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
3170 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
3171 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
3172 Rule Cuba 1965 only - Sep 30 0:00 0 S
3173 Rule Cuba 1966 only - May 29 0:00 1:00 D
3174 Rule Cuba 1966 only - Oct 2 0:00 0 S
3175 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
3176 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
3177 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
3178 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
3179 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
3180 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
3181 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
3182 Rule Cuba 1978 only - May 7 0:00 1:00 D
3183 Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S
3184 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
3185 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
3186 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
3187 Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D
3188 Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S
3189 Rule Cuba 1996 only - Oct 6 0:00s 0 S
3190 Rule Cuba 1997 only - Oct 12 0:00s 0 S
3191 Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D
3192 Rule Cuba 1998 2003 - Oct lastSun 0:00s 0 S
3193 Rule Cuba 2000 2003 - Apr Sun>=1 0:00s 1:00 D
3194 Rule Cuba 2004 only - Mar lastSun 0:00s 1:00 D
3195 Rule Cuba 2006 2010 - Oct lastSun 0:00s 0 S
3196 Rule Cuba 2007 only - Mar Sun>=8 0:00s 1:00 D
3197 Rule Cuba 2008 only - Mar Sun>=15 0:00s 1:00 D
3198 Rule Cuba 2009 2010 - Mar Sun>=8 0:00s 1:00 D
3199 Rule Cuba 2011 only - Mar Sun>=15 0:00s 1:00 D
3200 Rule Cuba 2011 only - Nov 13 0:00s 0 S
3201 Rule Cuba 2012 only - Apr 1 0:00s 1:00 D
3202 Rule Cuba 2012 max - Nov Sun>=1 0:00s 0 S
3203 Rule Cuba 2013 max - Mar Sun>=8 0:00s 1:00 D
3205 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3206 Zone America/Havana -5:29:28 - LMT 1890
3207 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT
3210 # Dominican Republic
3212 # From Steffen Thorsen (2000-10-30):
3213 # Enrique Morales reported to me that the Dominican Republic has changed the
3214 # time zone to Eastern Standard Time as of Sunday 29 at 2 am....
3215 # http://www.listin.com.do/antes/261000/republica/princi.html
3217 # From Paul Eggert (2000-12-04):
3218 # That URL (2000-10-26, in Spanish) says they planned to use US-style DST.
3220 # From Rives McDow (2000-12-01):
3221 # Dominican Republic changed its mind and presidential decree on Tuesday,
3222 # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the
3223 # Dominican Republic will be reverting to 8 hours from the International Date
3224 # Line, and will not be using DST in the foreseeable future. The reason they
3225 # decided to use DST was to be in synch with Puerto Rico, who was also going
3226 # to implement DST. When Puerto Rico didn't implement DST, the president
3227 # decided to revert.
3230 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3231 Rule DR 1966 only - Oct 30 0:00 1:00 EDT
3232 Rule DR 1967 only - Feb 28 0:00 0 EST
3233 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 -0430
3234 Rule DR 1970 only - Feb 21 0:00 0 EST
3235 Rule DR 1971 only - Jan 20 0:00 0 EST
3236 Rule DR 1972 1974 - Jan 21 0:00 0 EST
3237 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3238 Zone America/Santo_Domingo -4:39:36 - LMT 1890
3239 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
3240 -5:00 DR %s 1974 Oct 27
3241 -4:00 - AST 2000 Oct 29 2:00
3242 -5:00 US E%sT 2000 Dec 3 1:00
3247 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3248 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
3249 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
3250 # There are too many San Salvadors elsewhere, so use America/El_Salvador
3251 # instead of America/San_Salvador.
3252 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3253 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
3258 # From Gwillim Law (2006-04-22), after a heads-up from Oscar van Vlijmen:
3259 # Diario Co Latino, at
3260 # <http://www.diariocolatino.com/internacionales/detalles.asp?NewsID=8079>,
3261 # says in an article dated 2006-04-19 that the Guatemalan government had
3262 # decided on that date to advance official time by 60 minutes, to lessen the
3263 # impact of the elevated cost of oil.... Daylight saving time will last from
3264 # 2006-04-29 24:00 (Guatemalan standard time) to 2006-09-30 (time unspecified).
3265 # From Paul Eggert (2006-06-22):
3266 # The Ministry of Energy and Mines, press release CP-15/2006
3267 # (2006-04-19), says DST ends at 24:00. See
3268 # http://www.sieca.org.gt/Sitio_publico/Energeticos/Doc/Medidas/Cambio_Horario_Nac_190406.pdf
3270 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3271 Rule Guat 1973 only - Nov 25 0:00 1:00 D
3272 Rule Guat 1974 only - Feb 24 0:00 0 S
3273 Rule Guat 1983 only - May 21 0:00 1:00 D
3274 Rule Guat 1983 only - Sep 22 0:00 0 S
3275 Rule Guat 1991 only - Mar 23 0:00 1:00 D
3276 Rule Guat 1991 only - Sep 7 0:00 0 S
3277 Rule Guat 2006 only - Apr 30 0:00 1:00 D
3278 Rule Guat 2006 only - Oct 1 0:00 0 S
3279 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3280 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
3284 # From Gwillim Law (2005-04-15):
3285 # Risto O. Nykänen wrote me that Haiti is now on DST.
3286 # I searched for confirmation, and I found a press release
3287 # on the Web page of the Haitian Consulate in Chicago (2005-03-31),
3288 # <http://www.haitianconsulate.org/time.doc>. Translated from French, it says:
3290 # "The Prime Minister's Communication Office notifies the public in general
3291 # and the press in particular that, following a decision of the Interior
3292 # Ministry and the Territorial Collectivities [I suppose that means the
3293 # provinces], Haiti will move to Eastern Daylight Time in the night from next
3294 # Saturday the 2nd to Sunday the 3rd.
3296 # "Consequently, the Prime Minister's Communication Office wishes to inform
3297 # the population that the country's clocks will be set forward one hour
3298 # starting at midnight. This provision will hold until the last Saturday in
3301 # "Port-au-Prince, March 31, 2005"
3303 # From Steffen Thorsen (2006-04-04):
3304 # I have been informed by users that Haiti observes DST this year like
3305 # last year, so the current "only" rule for 2005 might be changed to a
3306 # "max" rule or to last until 2006. (Who knows if they will observe DST
3307 # next year or if they will extend their DST like US/Canada next year).
3309 # I have found this article about it (in French):
3310 # http://www.haitipressnetwork.com/news.cfm?articleID=7612
3312 # The reason seems to be an energy crisis.
3314 # From Stephen Colebourne (2007-02-22):
3315 # Some IATA info: Haiti won't be having DST in 2007.
3317 # From Steffen Thorsen (2012-03-11):
3318 # According to several news sources, Haiti will observe DST this year,
3319 # apparently using the same start and end date as USA/Canada.
3320 # So this means they have already changed their time.
3322 # http://www.alterpresse.org/spip.php?article12510
3323 # http://radiovision2000haiti.net/home/?p=13253
3325 # From Arthur David Olson (2012-03-11):
3326 # The alterpresse.org source seems to show a US-style leap from 2:00 a.m. to
3327 # 3:00 a.m. rather than the traditional Haitian jump at midnight.
3328 # Assume a US-style fall back as well.
3330 # From Steffen Thorsen (2013-03-10):
3331 # It appears that Haiti is observing DST this year as well, same rules
3332 # as US/Canada. They did it last year as well, and it looks like they
3333 # are going to observe DST every year now...
3335 # http://radiovision2000haiti.net/public/haiti-avis-changement-dheure-dimanche/
3336 # http://www.canalplushaiti.net/?p=6714
3338 # From Steffen Thorsen (2016-03-12):
3339 # Jean Antoine, editor of www.haiti-reference.com informed us that Haiti
3340 # are not going on DST this year. Several other resources confirm this: ...
3341 # https://www.radiotelevisioncaraibes.com/presse/heure_d_t_pas_de_changement_d_heure_pr_vu_pour_cet_ann_e.html
3342 # https://www.vantbefinfo.com/changement-dheure-pas-pour-haiti/
3343 # http://news.anmwe.com/haiti-lheure-nationale-ne-sera-ni-avancee-ni-reculee-cette-annee/
3345 # From Steffen Thorsen (2017-03-12):
3346 # We have received 4 mails from different people telling that Haiti
3347 # has started DST again today, and this source seems to confirm that,
3348 # I have not been able to find a more authoritative source:
3349 # https://www.haitilibre.com/en/news-20319-haiti-notices-time-change-in-haiti.html
3351 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3352 Rule Haiti 1983 only - May 8 0:00 1:00 D
3353 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
3354 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
3355 # Shanks & Pottenger say AT is 2:00, but IATA SSIM (1991/1997) says 1:00s.
3357 Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D
3358 Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S
3359 Rule Haiti 2005 2006 - Apr Sun>=1 0:00 1:00 D
3360 Rule Haiti 2005 2006 - Oct lastSun 0:00 0 S
3361 Rule Haiti 2012 2015 - Mar Sun>=8 2:00 1:00 D
3362 Rule Haiti 2012 2015 - Nov Sun>=1 2:00 0 S
3363 Rule Haiti 2017 max - Mar Sun>=8 2:00 1:00 D
3364 Rule Haiti 2017 max - Nov Sun>=1 2:00 0 S
3365 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3366 Zone America/Port-au-Prince -4:49:20 - LMT 1890
3367 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
3371 # Shanks & Pottenger say 1921 Jan 1; go with Whitman's more precise Apr 1.
3373 # From Paul Eggert (2006-05-05):
3374 # worldtimezone.com reports a 2006-05-02 Spanish-language AP article
3375 # saying Honduras will start using DST midnight Saturday, effective 4
3376 # months until September. La Tribuna reported today
3377 # <http://www.latribuna.hn/99299.html> that Manuel Zelaya, the president
3378 # of Honduras, refused to back down on this.
3380 # From Jesper Nørgaard Welen (2006-08-08):
3381 # It seems that Honduras has returned from DST to standard time this Monday at
3382 # 00:00 hours (prolonging Sunday to 25 hours duration).
3383 # http://www.worldtimezone.com/dst_news/dst_news_honduras04.html
3385 # From Paul Eggert (2006-08-08):
3386 # Also see Diario El Heraldo, The country returns to standard time (2006-08-08).
3387 # http://www.elheraldo.hn/nota.php?nid=54941&sec=12
3388 # It mentions executive decree 18-2006.
3390 # From Steffen Thorsen (2006-08-17):
3391 # Honduras will observe DST from 2007 to 2009, exact dates are not
3392 # published, I have located this authoritative source:
3393 # http://www.presidencia.gob.hn/noticia.aspx?nId=47
3395 # From Steffen Thorsen (2007-03-30):
3396 # http://www.laprensahn.com/pais_nota.php?id04962=7386
3397 # So it seems that Honduras will not enter DST this year....
3399 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3400 Rule Hond 1987 1988 - May Sun>=1 0:00 1:00 D
3401 Rule Hond 1987 1988 - Sep lastSun 0:00 0 S
3402 Rule Hond 2006 only - May Sun>=1 0:00 1:00 D
3403 Rule Hond 2006 only - Aug Mon>=1 0:00 0 S
3404 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3405 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
3408 # Great Swan I ceded by US to Honduras in 1972
3411 # Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an
3412 # unspecified official document, and says "This time is used throughout the
3413 # island". Go with Milne.
3415 # Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but
3416 # Lance Neita writes that Prime Minister Michael Manley decreed it January 5.
3417 # Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that
3418 # Manley's supporters associated this act with Manley's nickname "Joshua"
3419 # (recall that in the Bible the sun stood still at Joshua's request),
3420 # and with the Rod of Correction which Manley said he had received from
3421 # Haile Selassie, Emperor of Ethiopia. See:
3422 # Neita L. The politician in all of us. Jamaica Observer 2014-09-20
3423 # http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647
3425 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3427 Zone America/Jamaica -5:07:10 - LMT 1890 # Kingston
3428 -5:07:10 - KMT 1912 Feb # Kingston Mean Time
3434 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3435 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
3436 -4:04:20 - FFMT 1911 May # Fort-de-France MT
3437 -4:00 - AST 1980 Apr 6
3438 -4:00 1:00 ADT 1980 Sep 28
3443 # This uses Shanks & Pottenger for times before 2005.
3445 # From Steffen Thorsen (2005-04-12):
3446 # I've got reports from 8 different people that Nicaragua just started
3447 # DST on Sunday 2005-04-10, in order to save energy because of
3448 # expensive petroleum. The exact end date for DST is not yet
3449 # announced, only "September" but some sites also say "mid-September".
3450 # Some background information is available on the President's official site:
3451 # http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm
3452 # The Decree, no 23-2005 is available here:
3453 # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2005/Decreto%2023-2005%20Se%20adelanta%20en%20una%20hora%20en%20todo%20el%20territorio%20nacional%20apartir%20de%20las%2024horas%20del%2009%20de%20Abril.pdf
3455 # From Paul Eggert (2005-05-01):
3456 # The decree doesn't say anything about daylight saving, but for now let's
3457 # assume that it is daylight saving....
3459 # From Gwillim Law (2005-04-21):
3460 # The Associated Press story on the time change, which can be found at
3461 # http://www.lapalmainteractivo.com/guias/content/gen/ap/America_Latina/AMC_GEN_NICARAGUA_HORA.html
3462 # and elsewhere, says (fifth paragraph, translated from Spanish): "The last
3463 # time that a change of clocks was applied to save energy was in the year 2000
3464 # during the Arnoldo Alemán administration."...
3465 # The northamerica file says that Nicaragua has been on UTC-6 continuously
3466 # since December 1998. I wasn't able to find any details of Nicaraguan time
3467 # changes in 2000. Perhaps a note could be added to the northamerica file, to
3468 # the effect that we have indirect evidence that DST was observed in 2000.
3470 # From Jesper Nørgaard Welen (2005-11-02):
3471 # Nicaragua left DST the 2005-10-02 at 00:00 (local time).
3472 # http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm
3475 # From Jesper Nørgaard Welen (2006-05-05):
3476 # http://www.elnuevodiario.com.ni/2006/05/01/nacionales/18410
3477 # (my informal translation)
3478 # By order of the president of the republic, Enrique Bolaños, Nicaragua
3479 # advanced by sixty minutes their official time, yesterday at 2 in the
3480 # morning, and will stay that way until 30th of September.
3482 # From Jesper Nørgaard Welen (2006-09-30):
3483 # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2006/D-063-2006P-PRN-Cambio-Hora.pdf
3484 # My informal translation runs:
3485 # The natural sun time is restored in all the national territory, in that the
3486 # time is returned one hour at 01:00 am of October 1 of 2006.
3488 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S
3489 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
3490 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
3491 Rule Nic 2005 only - Apr 10 0:00 1:00 D
3492 Rule Nic 2005 only - Oct Sun>=1 0:00 0 S
3493 Rule Nic 2006 only - Apr 30 2:00 1:00 D
3494 Rule Nic 2006 only - Oct Sun>=1 1:00 0 S
3495 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3496 Zone America/Managua -5:45:08 - LMT 1890
3497 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time?
3498 -6:00 - CST 1973 May
3499 -5:00 - EST 1975 Feb 16
3500 -6:00 Nic C%sT 1992 Jan 1 4:00
3501 -5:00 - EST 1992 Sep 24
3509 # Atikokan and Coral Harbour, Canada, match Panama since 1970.
3510 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3511 Zone America/Panama -5:18:08 - LMT 1890
3512 -5:19:36 - CMT 1908 Apr 22 # Colón Mean Time
3518 # Caribbean Netherlands
3527 # Sint Maarten / St Martin
3529 # St Vincent & the Grenadines
3531 # Virgin Is (UK & US)
3533 # There are too many San Juans elsewhere, so we'll use 'Puerto_Rico'.
3534 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3535 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
3536 -4:00 - AST 1942 May 3
3540 # St Pierre and Miquelon
3541 # There are too many St Pierres elsewhere, so we'll use 'Miquelon'.
3542 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3543 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
3544 -4:00 - AST 1980 May
3546 -3:00 Canada -03/-02
3550 # From Chris Dunn in
3551 # https://bugs.debian.org/415007
3552 # (2007-03-15): In the Turks & Caicos Islands (America/Grand_Turk) the
3553 # daylight saving dates for time changes have been adjusted to match
3554 # the recent U.S. change of dates.
3556 # From Brian Inglis (2007-04-28):
3557 # http://www.turksandcaicos.tc/calendar/index.htm [2007-04-26]
3558 # there is an entry for Nov 4 "Daylight Savings Time Ends 2007" and three
3559 # rows before that there is an out of date entry for Oct:
3560 # "Eastern Standard Times Begins 2007
3561 # Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time"
3562 # indicating that the normal ET rules are followed.
3564 # From Paul Eggert (2014-08-19):
3565 # The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round. See:
3566 # http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm
3567 # Model this as a switch from EST/EDT to AST ...
3568 # From Chris Walton (2014-11-04):
3569 # ... the TCI government appears to have delayed the switch to
3570 # "permanent daylight saving time" by one year....
3571 # http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm
3573 # From the Turks & Caicos Cabinet (2017-07-20), heads-up from Steffen Thorsen:
3574 # ... agreed to the reintroduction in TCI of Daylight Saving Time (DST)
3575 # during the summer months and Standard Time, also known as Local
3576 # Time, during the winter months with effect from April 2018 ...
3577 # https://www.gov.uk/government/news/turks-and-caicos-post-cabinet-meeting-statement--3
3578 # From Paul Eggert (2017-08-26):
3579 # The date of effect of the spring 2018 change appears to be March 11,
3580 # which makes more sense. See: Hamilton D. Time change back
3581 # by March 2018 for TCI. Magnetic Media. 2017-08-25.
3582 # http://magneticmediatv.com/2017/08/time-change-back-by-march-2018-for-tci/
3584 # From P Chan (2020-11-27):
3585 # Standard Time Declaration Order 2015 (L.N. 15/2015)
3586 # http://online.fliphtml5.com/fizd/czin/#p=2
3588 # Standard Time Declaration Order 2017 (L.N. 31/2017)
3589 # http://online.fliphtml5.com/fizd/dmcu/#p=2
3591 # From Tim Parenti (2020-12-05):
3592 # Although L.N. 31/2017 reads that it "shall come into operation at 2:00 a.m.
3593 # on 11th March 2018", a precise interpretation here poses some problems. The
3594 # order states that "the standard time to be observed throughout the Turks and
3595 # Caicos Islands shall be the same time zone as the Eastern United States of
3596 # America" and further clarifies "[f]or the avoidance of doubt" that it
3597 # "applies to the Eastern Standard Time as well as any changes thereto for
3598 # Daylight Saving Time." However, as clocks in Turks and Caicos approached
3599 # 02:00 -04, and thus the declared implementation time, it was still 01:00 EST
3600 # (-05), as DST in the Eastern US would not start until an hour later.
3602 # Since it is unlikely that those on the islands switched their clocks twice in
3603 # the span of an hour, we assume instead that the adoption of EDT actually took
3604 # effect once clocks in the Eastern US had sprung forward, from 03:00 -04.
3605 # This discrepancy only affects the time zone abbreviation and DST flag for the
3606 # intervening hour, not wall clock times, as -04 was maintained throughout.
3608 # Zone NAME STDOFF RULES FORMAT [UNTIL]
3609 Zone America/Grand_Turk -4:44:32 - LMT 1890
3611 -5:07:10 - KMT 1912 Feb # Kingston Mean Time
3613 -5:00 US E%sT 2015 Mar 8 2:00
3614 -4:00 - AST 2018 Mar 11 3:00
projects / FreeBSD / FreeBSD.git / blob