1 # @(#)northamerica 7.15
2 # also includes Central America and the Caribbean
4 # This data is by no means authoritative; if you think you know better,
5 # go ahead and edit the file (and please send any changes to
6 # tz@elsie.nci.nih.gov for general use in the future).
8 # From Paul Eggert <eggert@twinsun.com> (August 17, 1994):
9 # A reliable and entertaining source about time zones is
10 # Derek Howse, Greenwich time and the discovery of the longitude,
11 # Oxford University Press (1980).
13 ###############################################################################
17 # From Arthur David Olson:
18 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
19 # See, for example, the front page of the Saturday, October 26, 1974
20 # and Sunday, October 27, 1974 editions of the Washington Post.
22 # From seismo!munnari!kre:
23 # I recall also being told by someone once that Canada didn't have
24 # the DST variations in 74/75 that the US did, but I am not nearly
25 # sure enough of this to add anything.
27 # From Arthur David Olson:
28 # The above has been confirmed by Bob Devine; we'll go with it here.
30 # From Arthur David Olson:
31 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
32 # Daylight Saving Time in the US was by local option, except during wartime.
34 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
35 Rule US 1918 1919 - Mar lastSun 2:00 1:00 D
36 Rule US 1918 1919 - Oct lastSun 2:00 0 S
37 Rule US 1942 only - Feb 9 2:00 1:00 W # War
38 Rule US 1945 only - Sep 30 2:00 0 S
39 Rule US 1967 max - Oct lastSun 2:00 0 S
40 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
41 Rule US 1974 only - Jan 6 2:00 1:00 D
42 Rule US 1975 only - Feb 23 2:00 1:00 D
43 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
44 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
46 # From Bob Devine (January 28, 1988):
47 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
49 # Pacific Standard Time(PST) -same-
50 # Yukon Standard Time(YST) -same-
51 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
52 # Nome Standard Time (NT) Bering Standard Time (BST)
54 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
55 # The YST zone now covers nearly all of the state, AHST just part
56 # of the Aleutian islands. No DST.
58 # From U. S. Naval Observatory (January 19, 1989):
59 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
60 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
61 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
62 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
63 # USA MOUNTAIN 7 H BEHIND UTC DENVER
64 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
65 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
66 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
67 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
68 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
69 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
70 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
71 # USA HAWAII 10 H BEHIND UTC
72 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
74 # From Arthur David Olson (January 21, 1989):
75 # The above dates are for 1988.
76 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
77 # no DST in Samoa, and the claim that there is DST in Alaska and the
80 # From Arthur David Olson (February 13, 1988):
81 # Legal standard time zone names, from United States Code (1982 Edition and
82 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
83 # up to April 1, 1967 (when most provisions of the Uniform Time Act of 1966
84 # took effect), as explained in sections 263 and 261:
86 # United States standard eastern time
87 # United States standard mountain time
88 # United States standard central time
89 # United States standard Pacific time
91 # United States standard Alaska time
93 # Next, names from April 1, 1967 until November 30, 1983 (the date for
95 # Atlantic standard time
96 # eastern standard time
97 # central standard time
98 # mountain standard time
99 # Pacific standard time
100 # Yukon standard time
101 # Alaska-Hawaii standard time
102 # Bering standard time
103 # And after November 30, 1983:
104 # Atlantic standard time
105 # eastern standard time
106 # central standard time
107 # mountain standard time
108 # Pacific standard time
109 # Alaska standard time
110 # Hawaii-Aleutian standard time
111 # Samoa standard time
112 # The law doesn't give abbreviations.
114 # From Paul Eggert <eggert@twinsun.com> (August 16, 1994):
115 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
116 # and from east-of-GMT to west-of-GMT days, in 1867 when the US purchased it
117 # from Russia. We don't have this data pinned down yet, though.
119 # Easy stuff first--including Alaska, where we ignore history (since we
120 # can't tell if we should give Yukon time or Alaska-Hawaii time for "old"
123 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
124 Zone America/New_York -5:00 US E%sT
125 Zone America/Chicago -6:00 US C%sT
126 Zone America/Denver -7:00 US M%sT
127 Zone America/Los_Angeles -8:00 US P%sT
128 Zone America/Anchorage -9:00 US AK%sT
129 # AK%sT is the abbreviation per USNO
131 # Mainland US areas that are always Standard as of 1986.
133 Zone America/Fort_Wayne -5:00 US E%sT 1946
134 -5:00 - EST # Always EST as of 1986
135 # From Arthur David Olson (October 28, 1991):
136 # An article on page A3 of the Sunday, October 27, 1991 Washington Post
137 # notes that Starke County switched from Central time to Eastern time as of
139 Zone America/Knox_IN -6:00 US C%sT 1991 Oct 27 2:00
140 -5:00 - EST # Always EST as of 1991
141 Zone America/Phoenix -7:00 US M%sT 1946
142 -7:00 - MST # Always MST as of 1986
144 # From Arthur David Olson (February 13, 1988):
145 # However. . .a writer from the Inter Tribal Council of Arizona, Inc.,
146 # notes in private correspondence dated 12/28/87 that "Presently, only the
147 # Navajo Nation participates in the Daylight Saving Time policy, due to its
148 # large size and location in three states." (The "only" means that other
149 # tribal nations don't use DST.)
151 Link America/Denver America/Shiprock
153 # From Bob Devine (January 28, 1988):
154 # Michigan didn't observe DST from 1968 to 1973.
156 Zone America/Detroit -5:00 US E%sT 1968
160 # Samoa just changes names. No DST, per Naval Observatory.
162 # Howse writes that in 1879 the King of Samoa decided to change
163 # ``the date in his kingdom from the Antipodean to the American system,
164 # ordaining -- by a masterpiece of diplomatic flattery -- that
165 # the Fourth of July should be celebrated twice in that year.''
167 Zone Pacific/Samoa 12:37:12 - LMT 1879 Jul 5
170 -11:00 - NST 1967 Apr # N=Nome
171 -11:00 - BST 1983 Nov 30 # B=Bering
172 -11:00 - SST # S=Samoa
174 Zone Pacific/Midway -11:49:28 - LMT 1901
175 -11:00 - NST 1967 Apr # N=Nome
176 -11:00 - BST 1983 Nov 30 # B=Bering
177 -11:00 - SST # S=Samoa
179 # Aleutian has a name change. DST, per Naval Observatory.
181 Zone America/Atka -10:00 US AH%sT 1983 Nov 30
184 # From Arthur David Olson:
185 # And then there's Hawaii.
186 # DST was observed for one day in 1933;
187 # Standard time was change by half an hour in 1947;
188 # it's always standard as of 1986.
190 Zone Pacific/Honolulu -10:30 US H%sT 1933 Apr 30 2:00
191 -10:30 1:00 HDT 1933 May 1 2:00
192 -10:30 US H%sT 1947 Jun 8 2:00
196 # no information; probably like US/Eastern
199 # Old names, for S5 users
201 # Link LINK-FROM LINK-TO
202 Link America/New_York EST5EDT
203 Link America/Chicago CST6CDT
204 Link America/Denver MST7MDT
205 Link America/Los_Angeles PST8PDT
206 Link America/Fort_Wayne EST
207 Link America/Phoenix MST
208 Link Pacific/Honolulu HST
210 ################################################################################
213 # From Paul Eggert <eggert@twinsun.com> (November 18, 1993):
214 # A good source for time zone historical data outside the U.S. is
215 # Thomas G. Shanks, The International Atlas (3rd edition),
216 # San Diego: ACS Publications, Inc. (1991).
217 # Except where otherwise noted, it is the source for the data below.
219 # Another source occasionally used is Edward W. Whitman, World Time Differences,
220 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
221 # I found in the UCLA library.
223 # I invented the abbreviation SPST for St Pierre Standard Time; SPDT likewise.
224 # Corrections are welcome!
226 # See the `europe' file for Greenland.
228 # See the `africa' file for Zone naming conventions.
234 # Canada is reportedly lots easier than the US--leastways since 1951.
235 # I don't know what they did before then.
236 # 4.3BSD claims that it's perfectly regular.
237 # According to a posting in "comp.bugs.misc", "comp.unix.wizards", etc.
238 # on February 8, 1987, by Dave Sherman of the Law Society of Upper Canada,
239 # "...Canada (well, Ontario and at least some of the other provinces) are
240 # adopting the new daylight savings time rules...". We assume all of
241 # Canada is doing so.
243 # From Bob Devine (January 28, 1988):
244 # All of Canada did have DST from your first rule except Saskatchewan.
245 # Which parts did not observe DST is hard to pinpoint but most of the
246 # province follows the rules.
247 # NOTE: those that didn't have DST for that rule, also
248 # probably did not have it for several years previous.
250 # From U. S. Naval Observatory (January 19, 1989):
251 # CANADA NEW FDL 3.5H BEHIND UTC ST.JOHN'S
252 # CANADA NEW FDL 1.5H BEHIND UTC APR 3 - OCT 29
253 # CANADA ATLANTIC 4 H BEHIND UTC HALIFAX
254 # CANADA ATLANTIC 3 H BEHIND UTC APR 3 - OCT 29
255 # CANADA EASTERN 5 H BEHIND UTC TORONTO, MONTREAL, OTTAWA
256 # CANADA EASTERN 4 H BEHIND UTC APR 3 - OCT 29
257 # CANADA CENTRAL 6 H BEHIND UTC REGINA, WINNIPEG
258 # CANADA CENTRAL 5 H BEHIND UTC APR 3 - OCT 29
259 # CANADA MOUNTAIN 7 H BEHIND UTC CALGARY, EDMONTON
260 # CANADA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 29
261 # CANADA PACIFIC 8 H BEHIND UTC VANCOUVER
262 # CANADA PACIFIC 7 H BEHIND UTC APR 3 - OCT 29
263 # CANADA YUKON SAME AS PACIFIC DAWSON
265 # From Arthur David Olson (January 21, 1989):
266 # April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
267 # Note claim that there's double DST in Newfoundland and that Yukon should
268 # be same as Pacific.
270 # From W. Jones (jones@skdad.usask.ca) (November 6, 1992):
271 # The. . .below is based on information I got from our law library, the
272 # provincial archives, and the provincial Community Services department.
273 # A precise history would require digging through newspaper archives, and
274 # since you didn't say what you wanted, I didn't bother.
276 # Saskatchewan is split by a time zone meridian (105W) and over the years
277 # the boundary became pretty ragged as communities near it reevaluated
278 # their affiliations in one direction or the other. In 1965 a provincial
279 # referendum favoured legislating common time practices.
281 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
282 # Saskatchewan 1978) was proclaimed, and established that the eastern
283 # part of Saskatchewan would use CST year round, that districts in
284 # northwest Saskatchewan would by default follow CST but could opt to
285 # follow Mountain Time rules (thus 1 hour difference in the winter and
286 # zero in the summer), and that districts in southwest Saskatchewan would
287 # by default follow MT but could opt to follow CST.
289 # It took a few years for the dust to settle (I know one story of a town
290 # on one time zone having its school in another, such that a mom had to
291 # serve her family lunch in two shifts), but presently it seems that only
292 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
293 # rules any more; all other districts appear to have used CST year round
294 # since sometime in the 1960s.
296 # Here's how I would summarize things. Establish a "Saskatchewan" CST
297 # time zone, and note that it officially exists as of 15 April 1966. Any
298 # current exceptions can put themselves in the "Mountain" zone, since
299 # those are the rules they follow. Any past exceptions can be forgotten,
300 # since that's what those who live here have done.
302 # From Arthur David Olson (November 21, 1992):
303 # East-Saskatchewan kept to avoid problems for folks using that zone by name;
304 # plain Saskatchewan added.
306 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
307 # I post here the time zone abbreviations standardized in Canada
308 # for both English and French in the CAN/CSA-Z234.4-89 standard....
310 # UTC Standard time Daylight savings time
311 # offset French English French English
322 # HN: Heure Normale ST: Standard Time
323 # HA: Heure Avanc<e'>e DT: Daylight saving Time
325 # A: de l'Atlantique Atlantic
326 # C: du Centre Central
327 # E: de l'Est Eastern
330 # P: du Pacifique Pacific
335 # From Paul Eggert <eggert@twinsun.com> (1994-11-22):
336 # Alas, this sort of thing must be handled by localization software.
340 # From Shanks (1991):
341 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
342 Rule StJohns 1884 only - Jan 1 0:00 0 S
343 Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D
344 Rule StJohns 1917 only - Sep 17 2:00 0 S
345 Rule StJohns 1918 only - Oct 31 2:00 0 S
346 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
347 Rule StJohns 1919 only - May 5 23:00 1:00 D
348 Rule StJohns 1919 only - Aug 12 23:00 0 S
349 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
350 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
351 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
352 # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman.
353 Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D
354 Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S
355 # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman.
356 Rule StJohns 1942 only - Mar 1 0:00 1:00 D
357 Rule StJohns 1942 only - Dec 31 0:00 0 S
358 Rule StJohns 1943 only - May 30 0:00 1:00 D
359 Rule StJohns 1943 only - Sep 5 0:00 0 S
360 Rule StJohns 1944 only - Jul 10 0:00 1:00 D
361 Rule StJohns 1944 only - Sep 2 0:00 0 S
362 Rule StJohns 1945 only - Jan 1 0:00 1:00 D
363 Rule StJohns 1945 only - Oct 7 2:00 0 S
364 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
365 # Apr 30 - Sep 24; go with Shanks.
366 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
367 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
368 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
369 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
370 Rule StJohns 1960 max - Oct lastSun 2:00 0 S
371 Rule StJohns 1987 only - Apr Sun>=1 2:00 1:00 D
372 Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 D
373 Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D
374 # St John's has an apostrophe, but Posix file names can't have apostrophes.
375 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
376 Zone America/St_Johns -3:30:52 - LMT 1884
377 -3:31 StJohns N%sT 1935 Mar 30
380 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
381 Rule Halifax 1902 only - Jun 15 0:00 0 S
382 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
383 Rule Halifax 1916 only - Oct 1 0:00 0 S
384 Rule Halifax 1918 only - Apr 14 2:00 1:00 D
385 Rule Halifax 1918 only - Oct 31 2:00 0 S
386 Rule Halifax 1920 only - May 9 0:00 1:00 D
387 Rule Halifax 1920 only - Aug 29 0:00 0 S
388 Rule Halifax 1921 only - May 6 0:00 1:00 D
389 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
390 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
391 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
392 Rule Halifax 1923 only - Sep 4 0:00 0 S
393 Rule Halifax 1924 only - Sep 15 0:00 0 S
394 Rule Halifax 1925 only - Sep 28 0:00 0 S
395 Rule Halifax 1926 only - May 16 0:00 1:00 D
396 Rule Halifax 1926 only - Sep 13 0:00 0 S
397 Rule Halifax 1927 only - May 1 0:00 1:00 D
398 Rule Halifax 1927 only - Sep 26 0:00 0 S
399 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
400 Rule Halifax 1928 only - Sep 9 0:00 0 S
401 Rule Halifax 1929 only - Sep 3 0:00 0 S
402 Rule Halifax 1930 only - Sep 15 0:00 0 S
403 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
404 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
405 Rule Halifax 1933 only - Oct 2 0:00 0 S
406 Rule Halifax 1934 only - May 20 0:00 1:00 D
407 Rule Halifax 1934 only - Sep 16 0:00 0 S
408 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
409 Rule Halifax 1935 only - Sep 30 0:00 0 S
410 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
411 Rule Halifax 1936 only - Sep 14 0:00 0 S
412 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
413 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
414 Rule Halifax 1939 only - May 28 0:00 1:00 D
415 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
416 Rule Halifax 1942 only - Feb 9 2:00 1:00 D
417 Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S
418 Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D
419 Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D
420 Rule Halifax 1962 max - Oct lastSun 2:00 0 S
421 Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D
422 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
423 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
426 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
427 Rule Mont 1884 only - Jan 1 0:00 0 S
428 Rule Mont 1917 only - Mar 25 2:00 1:00 D
429 Rule Mont 1917 only - Apr 24 0:00 0 S
430 Rule Mont 1918 only - Apr 14 2:00 1:00 D
431 Rule Mont 1918 only - Oct 31 2:00 0 S
432 Rule Mont 1919 only - Mar 31 2:30 1:00 D
433 Rule Mont 1919 only - Oct 25 2:30 0 S
434 Rule Mont 1920 only - May 2 2:30 1:00 D
435 Rule Mont 1920 only - Oct 3 2:30 0 S
436 Rule Mont 1921 only - May 1 2:00 1:00 D
437 Rule Mont 1921 only - Oct 2 2:30 0 S
438 Rule Mont 1922 only - Apr 30 2:00 1:00 D
439 Rule Mont 1922 only - Oct 1 2:30 0 S
440 Rule Mont 1924 only - May 17 2:00 1:00 D
441 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
442 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
443 Rule Mont 1927 only - May 1 0:00 1:00 D
444 Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S
445 Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D
446 Rule Mont 1932 only - May 1 0:00 1:00 D
447 Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D
448 Rule Mont 1933 only - Oct 1 0:00 0 S
449 Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S
450 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
451 Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D
452 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
453 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
454 Rule Mont 1957 max - Oct lastSun 2:00 0 S
455 Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D
456 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
457 Zone America/Montreal -4:54:16 - LMT 1884
460 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
461 Rule Winn 1887 only - Jul 16 0:00 0 S
462 Rule Winn 1916 only - Apr 23 0:00 1:00 D
463 Rule Winn 1916 only - Sep 17 0:00 0 S
464 Rule Winn 1918 only - Apr 14 2:00 1:00 D
465 Rule Winn 1918 only - Oct 31 2:00 0 S
466 Rule Winn 1937 only - May 16 2:00 1:00 D
467 Rule Winn 1937 only - Sep 23 2:00 0 S
468 Rule Winn 1942 only - Feb 9 2:00 1:00 D
469 Rule Winn 1945 only - Sep lastSun 2:00 0 S
470 Rule Winn 1946 only - May 12 2:00 1:00 D
471 Rule Winn 1946 only - Oct 13 2:00 0 S
472 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
473 Rule Winn 1947 1958 - Sep lastSun 2:00 0 S
474 Rule Winn 1948 only - May 1 2:00 1:00 D
475 Rule Winn 1948 1960 - Apr lastSun 2:00 1:00 D
476 Rule Winn 1959 only - Oct lastSun 2:00 0 S
477 Rule Winn 1960 only - Sep lastSun 2:00 0 S
478 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
479 Rule Winn 1963 only - Sep lastSun 2:00 0 S
480 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
481 Rule Winn 1966 max - Sep lastSun 2:00 0 S
482 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
483 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
484 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
487 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
488 Rule Regina 1905 only - Sep 1 0:00 0 S
489 Rule Regina 1918 only - Apr 14 2:00 1:00 D
490 Rule Regina 1918 only - Oct 31 2:00 0 S
491 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
492 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
493 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
494 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
495 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
496 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
497 Rule Regina 1942 only - Feb 9 2:00 1:00 D
498 Rule Regina 1945 only - Sep lastSun 2:00 0 S
499 Rule Regina 1946 only - Apr 14 2:00 1:00 D
500 Rule Regina 1946 only - Oct 13 2:00 0 S
501 Rule Regina 1947 1960 - Apr lastSun 2:00 1:00 D
502 Rule Regina 1947 1959 - Sep lastSun 2:00 0 S
503 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
504 Zone America/Regina -6:58:36 - LMT 1905 Sep
505 -7:00 Regina M%sT 1966 Apr 15
508 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
509 Rule Edm 1906 only - Sep 1 0:00 0 S
510 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
511 Rule Edm 1918 only - Oct 31 2:00 0 S
512 Rule Edm 1919 only - May 27 2:00 0 S
513 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
514 Rule Edm 1920 only - Oct lastSun 2:00 0 S
515 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
516 Rule Edm 1942 only - Feb 9 2:00 1:00 D
517 Rule Edm 1945 only - Sep lastSun 2:00 0 S
518 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
519 Rule Edm 1947 only - Sep lastSun 2:00 0 S
520 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
521 Rule Edm 1967 only - Oct lastSun 2:00 0 S
522 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
523 Rule Edm 1969 only - Oct lastSun 2:00 0 S
524 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
525 Rule Edm 1972 max - Oct lastSun 2:00 0 S
526 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
527 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
528 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
531 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
532 Rule Vanc 1884 only - Jan 1 0:00 0 S
533 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
534 Rule Vanc 1918 only - Oct 31 2:00 0 S
535 Rule Vanc 1942 only - Feb 9 2:00 1:00 D
536 Rule Vanc 1945 only - Sep 30 2:00 0 S
537 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
538 Rule Vanc 1946 only - Oct 13 2:00 0 S
539 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
540 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
541 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
542 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
543 Zone America/Vancouver -8:12:28 - LMT 1884
546 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
547 Rule Yukon 1900 only - Jan 1 0:00 0 S
548 Rule Yukon 1918 only - Apr 14 2:00 1:00 D
549 Rule Yukon 1918 only - Oct 27 2:00 0 S
550 Rule Yukon 1919 only - May 25 2:00 1:00 D
551 Rule Yukon 1919 only - Nov 1 0:00 0 S
552 Rule Yukon 1942 only - Feb 9 2:00 1:00 D
553 Rule Yukon 1965 only - Apr 25 0:00 1:00 D
554 Rule Yukon 1965 only - Oct 31 2:00 0 S
555 Rule Yukon 1980 1986 - Apr lastSun 2:00 1:00 D
556 Rule Yukon 1980 max - Oct lastSun 2:00 0 S
557 Rule Yukon 1987 max - Apr Sun>=1 2:00 1:00 D
558 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
559 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
560 -9:00 Yukon Y%sT 1966 Jul
562 # Parts of Yukon (e.g. Dawson) didn't switch to -8:00 until 1973 Oct 28.
564 ###############################################################################
569 # Rules are from the Official Airline Guide, Worldwide Edition, for 1987.
570 # Rules prior to 1987 are unknown.
571 # The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana
572 # observe DST." This is presumably Baja California Norte, above 28th parallel,
573 # as listed there; Mexico/BajaSur is for "Baja California Sur and N. Pacific
574 # Coast (States of Sinaloa and Sonora)."
576 # From Bob Devine (January 28, 1988):
577 # The Federal District (where Mexico City is) has observed [DST] several
578 # times but not recently.
580 # I don't where to drawn the line in the North Baja area. 28th latitude
581 # sounds good -- but it may be higher (how far [d]o radio stations from
582 # San Diego affect culture?).
584 # The dates of DST probably go back to 1981. The rules are the same as
585 # US's. This is going to be a headache for US presidential electi[o]n years!
587 # From Arthur David Olson (February 13, 1988)
588 # Since the 1981 starting date is only "probable," we'll keep the 1987
589 # starting date below.
591 # From U. S. Naval Observatory (January 19, 1989):
592 # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND
593 # MEXICO BAJA CAL N N. PACIFIC COAST (STATES
594 # MEXICO BAJA CAL N OF SINALOA AND SONORA)
595 # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
596 # MEXICO BAJA CAL N - OCT 29
597 # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
598 # MEXICO BAJA CAL N - 0CT 29
599 # MEXICO 6 H BEHIND UTC STATES OF DURANGO,
600 # MEXICO COAHUILA, NUEVO LEON,
602 # MEXICO 5 H BEHIND UTC STATES OF DURANGO,
603 # MEXICO COAHUILA, NUEVO LEON,
604 # MEXICO TAMAULIPAS APR 3 - OCT 29
605 # MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF
606 # MEXICO CAMPECHE, QUINTANA ROO AND
609 # From Arthur David Olson (January 21, 1989):
610 # April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
611 # USNO claims there should be four Mexican zones rather than three:
612 # a zone that's GMT-8 with DST; a zone that's always GMT-7;
613 # a zone that's GMT-6 with DST; and a zone that's always GMT-6.
615 # From Paul Eggert <eggert@twinsun.com> (November 18, 1993):
616 # Shanks also says there are four zones, but disagrees about the fourth.
617 # Instead of GMT-6 with DST, he says there's GMT-8 without DST.
619 # From Shanks (1991):
620 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
621 Rule Mexico 1922 only - Jan 1 0:00 0 S
622 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
623 Rule Mexico 1939 only - Jun 25 0:00 0 S
624 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
625 Rule Mexico 1941 only - Apr 1 0:00 0 S
626 Rule Mexico 1943 only - Dec 16 0:00 1:00 D
627 Rule Mexico 1944 only - May 1 0:00 0 S
628 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
629 Rule Mexico 1950 only - Jul 30 0:00 0 S
630 Rule BajaN 1950 1966 - Apr lastSun 2:00 1:00 D
631 Rule BajaN 1950 1961 - Sep lastSun 2:00 0 S
632 Rule BajaN 1961 1966 - Oct lastSun 2:00 0 S
633 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
634 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
635 -7:00 - MST 1927 Jun 10 23:00
636 -6:00 - CST 1930 Nov 15
637 -7:00 - MST 1931 May 1 23:00
639 -7:00 - MST 1932 Mar 30 23:00
641 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
642 -7:00 - MST 1927 Jun 10 23:00
643 -6:00 - CST 1930 Nov 15
644 -7:00 - MST 1931 May 1 23:00
646 -7:00 - MST 1932 Mar 30 23:00
648 -7:00 - MST 1949 Jan 14
651 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
652 -8:00 - PST 1927 Jun 10 23:00
653 -7:00 - MST 1930 Nov 16
655 -7:00 - MST 1949 Jan 14
656 -8:00 BajaN P%sT 1967 Apr lastSun 2:00
658 Zone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32
659 -8:00 - PST 1927 Jun 10 23:00
660 -7:00 - MST 1930 Nov 16
662 -7:00 - MST 1949 Jan 14
668 ###############################################################################
671 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
672 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
675 # Antigua and Barbuda
676 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
677 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
682 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
683 Rule Bahamas 1912 only - Mar 2 0:00 0 S
684 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
685 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
686 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
687 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
688 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
692 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
693 Rule Barb 1932 only - Jan 1 0:00 0 S
694 Rule Barb 1977 only - Jun 12 2:00 1:00 D
695 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
696 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
697 Rule Barb 1979 only - Sep 30 2:00 0 S
698 Rule Barb 1980 only - Sep 25 2:00 0 S
699 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
700 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
701 -3:58 - BMT 1932 # Bridgetown Mean Time
705 # Whitman entirely disagrees with Shanks; go with Shanks.
706 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
707 Rule Belize 1912 only - Apr 1 0:00 0 S
708 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
709 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
710 Rule Belize 1973 only - Dec 5 0:00 1:00 D
711 Rule Belize 1974 only - Feb 9 0:00 0 S
712 Rule Belize 1982 only - Dec 18 0:00 1:00 D
713 Rule Belize 1983 only - Feb 12 0:00 0 S
714 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
715 Zone America/Belize -5:52:48 - LMT 1912 Apr
719 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
720 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
721 -4:00 - AST 1974 Apr 28 2:00
725 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
726 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
727 -5:07 - KMT 1912 Feb # Kingston Mean Time
734 # Shanks gives some very odd dates for 1991, and stops there.
735 # For now, we won't guess further.
736 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
737 Rule CR 1921 only - Jan 15 0:00 0 S
738 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
739 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
740 Rule CR 1991 only - Jan 19 0:00 1:00 D
741 Rule CR 1991 only - Jul 1 0:00 0 S
742 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
743 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
744 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
745 -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time
748 # no information; probably like America/Costa_Rica
752 # From Bob Devine (January 28, 1988):
753 # . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981.
754 # Change at midnight. In 1979 & 1980, started at 3rd Sunday in March
757 # From U. S. Naval Observatory (January 19, 1989):
758 # CUBA 5 H BEHIND UTC
759 # CUBA 4 H BEHIND UTC MAR 20 - OCT 8
761 # From Shanks (1991):
762 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
763 Rule Cuba 1925 only - Jul 19 12:00 0 S
764 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
765 Rule Cuba 1928 only - Oct 10 0:00 0 S
766 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
767 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
768 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
769 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
770 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
771 Rule Cuba 1965 only - Sep 30 0:00 0 S
772 Rule Cuba 1966 only - May 29 0:00 1:00 D
773 Rule Cuba 1966 only - Oct 2 0:00 0 S
774 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
775 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
776 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
777 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
778 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
779 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
780 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
781 Rule Cuba 1978 only - May 7 0:00 1:00 D
782 Rule Cuba 1978 1980 - Oct Sun>=8 0:00 0 S
783 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
784 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
785 Rule Cuba 1981 max - Oct Sun>=8 0:00 0 S
786 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
787 Rule Cuba 1990 only - Apr 1 0:00 1:00 D
788 Rule Cuba 1991 max - Mar Sun>=14 0:00 1:00 D
790 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
791 Zone America/Havana -5:29:28 - LMT 1890
792 -5:30 - HMT 1925 Jul 19 12:00 # Havana MT
796 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
797 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
801 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
802 Rule DR 1933 only - Apr 1 12:00 0 S
803 Rule DR 1966 only - Oct 30 0:00 1:00 D
804 Rule DR 1967 only - Feb 28 0:00 0 S
805 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
806 Rule DR 1970 only - Feb 21 0:00 0 S
807 Rule DR 1971 only - Jan 20 0:00 0 S
808 Rule DR 1972 1974 - Jan 21 0:00 0 S
809 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
810 Zone America/Santo_Domingo -4:39:36 - LMT 1890
811 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
812 -5:00 DR E%sT 1974 Oct 27
816 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
817 Rule Salv 1921 only - Jan 1 0:00 0 S
818 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
819 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
820 # There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
821 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
822 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
826 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
827 Zone America/Grenada -4:07:00 - LMT 1911 Jul
831 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
832 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
836 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
837 Rule Guat 1918 only - Oct 5 0:00 0 S
838 Rule Guat 1973 only - Nov 25 0:00 1:00 D
839 Rule Guat 1974 only - Feb 24 0:00 0 S
840 Rule Guat 1983 only - May 21 0:00 1:00 D
841 Rule Guat 1983 only - Sep 22 0:00 0 S
842 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
843 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
847 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
848 Rule Haiti 1917 only - Jan 24 12:00 0 S
849 Rule Haiti 1983 only - May 8 0:00 1:00 D
850 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
851 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
852 Rule Haiti 1988 max - Apr Sun>=1 2:00 1:00 D
853 Rule Haiti 1988 max - Oct lastSun 2:00 0 S
854 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
855 Zone America/Port-au-Prince -4:49:20 - LMT 1890
856 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
860 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
861 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
862 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
867 # From Bob Devine (January 28, 1988):
870 # From U. S. Naval Observatory (January 19, 1989):
871 # JAMAICA 5 H BEHIND UTC
873 # From Shanks (1991):
874 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
875 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
876 -5:07 - KMT 1912 Feb # Kingston Mean Time
877 -5:00 - EST 1974 Jan 6 2:00
881 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
882 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
883 -4:04 - FFMT 1911 May # Fort-de-France MT
884 -4:00 - AST 1980 Apr 6
885 -4:00 1:00 ADT 1980 Sep 28
889 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
890 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Plymouth
894 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
895 Rule Nic 1975 only - Feb 16 0:00 0 S
896 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
897 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
898 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
899 Zone America/Managua -5:45:08 - LMT 1890
900 -5:45 - MMT 1934 Jun 23 # Managua Mean Time
902 -5:00 - EST 1975 Feb 16
906 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
907 Zone America/Panama -5:18:08 - LMT 1890
908 -5:20 - PMT 1908 Apr 22 # Panama Mean Time
912 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
913 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
914 Zone America/Puerto_Rico -4:24:28 - LMT 1899 Mar 28 12:00 # San Juan
915 -4:00 - AST 1942 May 3
916 -4:00 1:00 ADT 1945 Sep 30 2:00
920 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
921 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
925 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
926 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
927 -4:04 - CMT 1912 # Castries Mean Time
930 # St Pierre and Miquelon
931 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
932 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
933 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
937 # St Vincent and the Grenadines
938 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
939 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
940 -4:05 - KMT 1912 # Kingstown Mean Time
944 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
945 Zone America/Grand_Turk -4:44:32 - LMT 1890
946 -5:07 - KMT 1912 Feb # Kingston Mean Time
947 -5:00 - EST 1979 Apr 29 2:00
950 # Virgin Is (British and US)
951 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
952 Zone America/Virgin -4:19:44 - LMT 1911 Jul # Charlotte Amalie