| blob | 57719816f9bba54fadb1a75ce7b504c82f455da2 |
1 # @(#)northamerica 7.26
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 ###############################################################################
15 # United States
17 # From Paul Eggert <eggert@twinsun.com> (1995-12-19):
18 # A good source for time zone historical data in the US is
19 # Thomas G. Shanks, The American Atlas (5th edition),
20 # San Diego: ACS Publications, Inc. (1991).
21 # Make sure you have the errata sheet; the book is somewhat useless without it.
22 # It is the source for the US and Puerto Rico entries below.
24 # From Paul Eggert (1996-06-12):
25 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
26 # in his whimsical essay ``Turkey vs Eagle, McCauley is my Beagle'' (1784).
27 # Not everyone is happy with the results:
28 #
29 # I don't really care how time is reckoned so long as there is some
30 # agreement about it, but I object to being told that I am saving
31 # daylight when my reason tells me that I am doing nothing of the kind.
32 # I even object to the implication that I am wasting something
33 # valuable if I stay in bed after the sun has risen. As an admirer
34 # of moonlight I resent the bossy insistence of those who want to
35 # reduce my time for enjoying it. At the back of the Daylight Saving
36 # scheme I detect the bony, blue-fingered hand of Puritanism, eager
37 # to push people into bed earlier, and get them up earlier, to make
38 # them healthy, wealthy and wise in spite of themselves.
39 #
40 # -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday
42 # From Arthur David Olson:
43 # US Daylight Saving Time ended on the last Sunday of *October* in 1974.
44 # See, for example, the front page of the Saturday, October 26, 1974
45 # and Sunday, October 27, 1974 editions of the Washington Post.
47 # From Arthur David Olson:
48 # Before the Uniform Time Act of 1966 took effect in 1967, observance of
49 # Daylight Saving Time in the US was by local option, except during wartime.
51 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
52 Rule US 1918 1919 - Mar lastSun 2:00 1:00 W # War
53 Rule US 1918 1919 - Oct lastSun 2:00 0 S
54 Rule US 1942 only - Feb 9 2:00 1:00 W # War
55 Rule US 1945 only - Sep 30 2:00 0 S
56 Rule US 1967 max - Oct lastSun 2:00 0 S
57 Rule US 1967 1973 - Apr lastSun 2:00 1:00 D
58 Rule US 1974 only - Jan 6 2:00 1:00 D
59 Rule US 1975 only - Feb 23 2:00 1:00 D
60 Rule US 1976 1986 - Apr lastSun 2:00 1:00 D
61 Rule US 1987 max - Apr Sun>=1 2:00 1:00 D
63 # From Bob Devine (January 28, 1988):
64 # ...Alaska (and Hawaii) had the timezone names changed in 1967.
65 # old new
66 # Pacific Standard Time(PST) -same-
67 # Yukon Standard Time(YST) -same-
68 # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST)
69 # Nome Standard Time (NT) Bering Standard Time (BST)
70 #
71 # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz.
72 # The YST zone now covers nearly all of the state, AHST just part
73 # of the Aleutian islands. No DST.
75 # From Paul Eggert (1995-12-19):
76 # The tables below use `NST', not `NT', for Nome Standard Time.
77 # I invented `CAWT' for Central Alaska War Time.
79 # From U. S. Naval Observatory (January 19, 1989):
80 # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON
81 # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30
82 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON
83 # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30
84 # USA MOUNTAIN 7 H BEHIND UTC DENVER
85 # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30
86 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO
87 # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30
88 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST)
89 # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT)
90 # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W
91 # USA - " - 9 H BEHIND UTC APR 3 - OCT 30
92 # USA HAWAII 10 H BEHIND UTC
93 # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY
95 # From Arthur David Olson (January 21, 1989):
96 # The above dates are for 1988.
97 # Note the "AKST" and "AKDT" abbreviations, the claim that there's
98 # no DST in Samoa, and the claim that there is DST in Alaska and the
99 # Aleutians.
101 # From Arthur David Olson (February 13, 1988):
102 # Legal standard time zone names, from United States Code (1982 Edition and
103 # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names
104 # up to April 1, 1967 (when most provisions of the Uniform Time Act of 1966
105 # took effect), as explained in sections 263 and 261:
106 # (none)
107 # United States standard eastern time
108 # United States standard mountain time
109 # United States standard central time
110 # United States standard Pacific time
111 # (none)
112 # United States standard Alaska time
113 # (none)
114 # Next, names from April 1, 1967 until November 30, 1983 (the date for
115 # public law 98-181):
116 # Atlantic standard time
117 # eastern standard time
118 # central standard time
119 # mountain standard time
120 # Pacific standard time
121 # Yukon standard time
122 # Alaska-Hawaii standard time
123 # Bering standard time
124 # And after November 30, 1983:
125 # Atlantic standard time
126 # eastern standard time
127 # central standard time
128 # mountain standard time
129 # Pacific standard time
130 # Alaska standard time
131 # Hawaii-Aleutian standard time
132 # Samoa standard time
133 # The law doesn't give abbreviations.
134 #
135 # From Paul Eggert (1995-12-19):
136 # Shanks uses 1983-10-30, not 1983-11-30, for the 1983 transitions.
137 # Go with Shanks.
139 # US Eastern time, represented by New York
140 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
141 Rule NYC 1920 only - Mar lastSun 2:00 1:00 D
142 Rule NYC 1920 only - Oct lastSun 2:00 0 S
143 Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D
144 Rule NYC 1921 1954 - Sep lastSun 2:00 0 S
145 Rule NYC 1955 1966 - Oct lastSun 2:00 0 S
146 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
147 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00
148 -5:00 US E%sT 1920
149 -5:00 NYC E%sT 1942
150 -5:00 US E%sT 1946
151 -5:00 NYC E%sT 1967
152 -5:00 US E%sT
154 # US Central time, represented by Chicago
155 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
156 Rule Chicago 1920 only - Jun 13 2:00 1:00 D
157 Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S
158 Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D
159 Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D
160 Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S
161 Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S
162 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
163 Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00
164 -6:00 US C%sT 1920
165 -6:00 Chicago C%sT 1936 Mar 1 2:00
166 -5:00 - EST 1936 Nov 15 2:00
167 -6:00 Chicago C%sT 1942
168 -6:00 US C%sT 1946
169 -6:00 Chicago C%sT 1967
170 -6:00 US C%sT
172 # US Mountain time, represented by Denver
173 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
174 Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D
175 Rule Denver 1920 only - Oct lastSun 2:00 0 S
176 Rule Denver 1921 only - May 22 2:00 0 S
177 Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D
178 Rule Denver 1965 1966 - Oct lastSun 2:00 0 S
179 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
180 Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00
181 -7:00 US M%sT 1920
182 -7:00 Denver M%sT 1942
183 -7:00 US M%sT 1946
184 -7:00 Denver M%sT 1967
185 -7:00 US M%sT
187 # US Pacific time, represented by Los Angeles
188 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
189 Rule CA 1948 only - Mar 14 2:00 1:00 D
190 Rule CA 1949 only - Jan 1 2:00 0 S
191 Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D
192 Rule CA 1950 1961 - Sep lastSun 2:00 0 S
193 Rule CA 1962 1966 - Oct lastSun 2:00 0 S
194 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
195 Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00
196 -8:00 US P%sT 1946
197 -8:00 CA P%sT 1967
198 -8:00 US P%sT
200 # Alaska
201 # AK%sT is the modern abbreviation for -9:00 per USNO.
202 #
203 # From Paul Eggert (1995-12-19):
204 # Howse writes that Alaska switched from the Julian to the Gregorian calendar,
205 # and from east-of-GMT to west-of-GMT days, in 1867 when the US purchased it
206 # from Russia. We omit this transition, since we can't represent changes
207 # from Julian to Gregorian.
208 #
209 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
210 Zone America/Juneau -8:57:41 - LMT 1900 Aug 20 12:00
211 -8:00 - PST 1942
212 -8:00 US P%sT 1946
213 -8:00 - PST 1969
214 -8:00 US P%sT 1983 Oct 30 2:00
215 -9:00 US AK%sT
216 Zone America/Yakutat -9:18:55 - LMT 1900 Aug 20 12:00
217 -9:00 - YST 1942
218 -9:00 US Y%sT 1946
219 -9:00 - YST 1969
220 -9:00 US Y%sT 1983 Oct 30 2:00
221 -9:00 US AK%sT
222 Zone America/Anchorage -9:59:36 - LMT 1900 Aug 20 12:00
223 -10:00 - CAT 1942
224 -10:00 US CAT/CAWT 1946
225 -10:00 - CAT 1967 Apr
226 -10:00 - AHST 1969
227 -10:00 US AH%sT 1983 Oct 30 2:00
228 -9:00 US AK%sT
229 Zone America/Nome -11:01:38 - LMT 1900 Aug 20 12:00
230 -11:00 - NST 1942
231 -11:00 US N%sT 1946
232 -11:00 - NST 1967 Apr
233 -11:00 - BST 1969
234 -11:00 US B%sT 1983 Oct 30 2:00
235 -9:00 US AK%sT
236 Zone America/Adak -11:46:38 - LMT 1900 Aug 20 12:00
237 -11:00 - NST 1942
238 -11:00 US N%sT 1946
239 -11:00 - NST 1967 Apr
240 -11:00 - BST 1969
241 -11:00 US B%sT 1983 Oct 30 2:00
242 -10:00 US HA%sT
243 # Shanks writes that part of southwest Alaska (e.g. Aniak)
244 # switched from -11:00 to -10:00 on 1968-09-22 at 02:00,
245 # and another part (e.g. Akiak) made the same switch five weeks later.
246 # These switches don't quite make our 1970 cutoff.
248 # Hawaii
249 #
250 # From Arthur David Olson:
251 # And then there's Hawaii.
252 # DST was observed for one day in 1933;
253 # standard time was changed by half an hour in 1947;
254 # it's always standard as of 1986.
255 #
256 # From Paul Eggert:
257 # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks.
258 #
259 Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00
260 -10:30 - HST 1933 Apr 30 2:00
261 -10:30 1:00 HDT 1933 May 21 2:00
262 -10:30 US H%sT 1947 Jun 8 2:00
263 -10:00 - HST
265 Zone Pacific/Midway -11:49:28 - LMT 1901
266 -11:00 - NST 1967 Apr # N=Nome
267 -11:00 - BST 1983 Nov 30 # B=Bering
268 -11:00 - SST # S=Samoa
270 # Now we turn to US areas that have diverged from the consensus since 1970.
272 # Arizona mostly uses MST.
273 Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00
274 -7:00 US M%sT 1944 Jan 1 00:01
275 -7:00 - MST 1944 Mar 17 00:01
276 -7:00 US M%sT 1944 Oct 1 00:01
277 -7:00 - MST 1967
278 -7:00 US M%sT 1968
279 -7:00 - MST
280 # From Arthur David Olson (February 13, 1988):
281 # A writer from the Inter Tribal Council of Arizona, Inc.,
282 # notes in private correspondence dated 12/28/87 that "Presently, only the
283 # Navajo Nation participates in the Daylight Saving Time policy, due to its
284 # large size and location in three states." (The "only" means that other
285 # tribal nations don't use DST.)
287 Link America/Denver America/Shiprock
289 # Southern Idaho and eastern Oregon switched four weeks late in 1974.
290 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
291 Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00
292 -8:00 US P%sT 1923 May 13 2:00
293 -7:00 US M%sT 1974
294 -7:00 - MST 1974 Feb 3 2:00
295 -7:00 US M%sT
297 # Indiana
298 #
299 # From Paul Eggert (1995-12-19):
300 # Indiana generally observes either EST all year, or CST/CDT,
301 # but areas near Cincinnati and Louisville use those cities' timekeeping
302 # and in 1969 and 1970 the whole state observed daylight time;
303 # and there are other exceptions as noted below.
304 # Shanks partitions Indiana into 345 regions, each with its own time history,
305 # and writes ``Even newspaper reports present contradictory information.''
306 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
307 #
308 # Since 1970, EST-only Indiana has been like America/Indianapolis,
309 # with exceptions noted below for Crawford, Starke, and Switzerland counties.
310 # The parts of Indiana not listed below have been like America/Chicago,
311 # America/Louisville, or America/New_York.
312 #
313 # Other than Indianapolis, the Indiana place names are so nondescript
314 # that they would be ambiguous if we left them at the `America' level.
315 # So we reluctantly put them all in a subdirectory `America/Indiana'.
316 #
317 # Most of EST-only Indiana last observed DST in 1970.
318 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
319 Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D
320 Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S
321 Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D
322 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
323 Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:00
324 -6:00 US C%sT 1920
325 -6:00 Indianapolis C%sT 1942
326 -6:00 US C%sT 1946
327 -6:00 Indianapolis C%sT 1955 Apr 24 2:00
328 -5:00 - EST 1957 Sep 29 2:00
329 -6:00 - CST 1958 Apr 27 2:00
330 -5:00 - EST 1969
331 -5:00 US E%sT 1971
332 -5:00 - EST
333 Link America/Indianapolis America/Indiana/Indianapolis
334 #
335 # Part of Crawford County, Indiana, last observed DST in 1975,
336 # and left its clocks alone in 1974.
337 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
338 Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D
339 Rule Marengo 1951 only - Sep lastSun 2:00 0 S
340 Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D
341 Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S
342 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
343 Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00
344 -6:00 US C%sT 1951
345 -6:00 Marengo C%sT 1961 Apr 30 2:00
346 -5:00 - EST 1969
347 -5:00 US E%sT 1974 Jan 6 2:00
348 -6:00 1:00 CDT 1974 Oct 27 2:00
349 -5:00 US E%sT 1976
350 -5:00 - EST
351 #
352 # Starke County, Indiana
353 # From Arthur David Olson (October 28, 1991):
354 # An article on page A3 of the Sunday, October 27, 1991 Washington Post
355 # notes that Starke County switched from Central time to Eastern time as of
356 # October 27, 1991.
357 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
358 Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D
359 Rule Starke 1947 1954 - Sep lastSun 2:00 0 S
360 Rule Starke 1955 1956 - Oct lastSun 2:00 0 S
361 Rule Starke 1957 1958 - Sep lastSun 2:00 0 S
362 Rule Starke 1959 1961 - Oct lastSun 2:00 0 S
363 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
364 Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00
365 -6:00 US C%sT 1947
366 -6:00 Starke C%sT 1962 Apr 29 2:00
367 -5:00 - EST 1963 Oct 27 2:00
368 -6:00 US C%sT 1991 Oct 27 2:00
369 -5:00 - EST
370 #
371 # Switzerland County, Indiana, last observed DST in 1972.
372 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
373 Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00
374 -6:00 US C%sT 1954 Apr 25 2:00
375 -5:00 - EST 1969
376 -5:00 US E%sT 1973
377 -5:00 - EST
379 # Part of Kentucky left its clocks alone in 1974.
380 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
381 Rule Louisville 1921 only - May 1 2:00 1:00 D
382 Rule Louisville 1921 only - Sep 1 2:00 0 S
383 Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D
384 Rule Louisville 1941 only - Sep lastSun 2:00 0 S
385 Rule Louisville 1946 only - Jun 2 2:00 0 S
386 Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S
387 Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S
388 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
389 Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:00
390 -6:00 US C%sT 1921
391 -6:00 Louisville C%sT 1942
392 -6:00 US C%sT 1946
393 -6:00 Louisville C%sT 1961 Jul 23 2:00
394 -5:00 - EST 1968
395 -5:00 US E%sT 1974 Jan 6 2:00
396 -6:00 1:00 CDT 1974 Oct 27 2:00
397 -5:00 US E%sT
399 # Michigan
400 #
401 # From Bob Devine (January 28, 1988):
402 # Michigan didn't observe DST from 1968 to 1973.
403 #
404 # From Paul Eggert (1995-12-19):
405 # Shanks writes that Michigan started using standard time on 1885 Sep 18,
406 # but Howse (p 126) writes that Detroit kept
407 #
408 # local time until 1900 when the City Council decreed that clocks should
409 # be put back twenty-eight minutes to Central Standard Time. Half the
410 # city obeyed, half refused. After considerable debate, the decision
411 # was rescinded and the city reverted to Sun time. A derisive offer to
412 # erect a sundial in front of the city hall was referred to the
413 # Committee on Sewers. Then, in 1905, Central time was adopted
414 # by city vote.
415 #
416 # This story is too entertaining to be false, so go with Howse over Shanks.
417 #
418 # Most of Michigan observed DST from 1973 on, but was a bit late in 1975.
419 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
420 Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D
421 Rule Detroit 1948 only - Sep lastSun 2:00 0 S
422 Rule Detroit 1967 only - Jun 14 2:00 1:00 D
423 Rule Detroit 1967 only - Oct lastSun 2:00 0 S
424 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
425 Zone America/Detroit -5:32:11 - LMT 1905
426 -6:00 - CST 1915 May 15 2:00
427 -5:00 - EST 1942
428 -5:00 US E%sT 1946
429 -5:00 Detroit E%sT 1973
430 -5:00 US E%sT 1975
431 -5:00 - EST 1975 Apr 27 2:00
432 -5:00 US E%sT
433 #
434 # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973.
435 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER
436 Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D
437 Rule Menominee 1946 only - Sep lastSun 2:00 0 S
438 Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D
439 Rule Menominee 1966 only - Oct lastSun 2:00 0 S
440 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
441 Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00
442 -6:00 US C%sT 1946
443 -6:00 Menominee C%sT 1969 Apr 27 2:00
444 -5:00 - EST 1973 Apr 29 2:00
445 -6:00 US C%sT
447 # Navassa
448 # uninhabited
451 # Old names, for S5 users
453 # Link LINK-FROM LINK-TO
454 Link America/New_York EST5EDT
455 Link America/Chicago CST6CDT
456 Link America/Denver MST7MDT
457 Link America/Los_Angeles PST8PDT
458 Link America/Indianapolis EST
459 Link America/Phoenix MST
460 Link Pacific/Honolulu HST
462 ################################################################################
465 # From Paul Eggert <eggert@twinsun.com> (November 18, 1993):
466 # A good source for time zone historical data outside the US is
467 # Thomas G. Shanks, The International Atlas (3rd edition),
468 # San Diego: ACS Publications, Inc. (1991).
469 # Except where otherwise noted, it is the source for the data below.
470 #
471 # Another source occasionally used is Edward W. Whitman, World Time Differences,
472 # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which
473 # I found in the UCLA library.
474 #
475 # I invented the abbreviation SPST for St Pierre Standard Time; SPDT likewise.
476 # Corrections are welcome!
477 #
478 # See the `europe' file for Greenland.
479 #
480 # See the `africa' file for Zone naming conventions.
482 # Canada
484 # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14):
485 # I post here the time zone abbreviations standardized in Canada
486 # for both English and French in the CAN/CSA-Z234.4-89 standard....
487 #
488 # UTC Standard time Daylight savings time
489 # offset French English French English
490 # -2:30 - - HAT NDT
491 # -3 - - HAA ADT
492 # -3:30 HNT NST - -
493 # -4 HNA AST HAE EDT
494 # -5 HNE EST HAC CDT
495 # -6 HNC CST HAR MDT
496 # -7 HNR MST HAP PDT
497 # -8 HNP PST HAY YDT
498 # -9 HNY YST - -
499 #
500 # HN: Heure Normale ST: Standard Time
501 # HA: Heure Avanc<e'>e DT: Daylight saving Time
502 #
503 # A: de l'Atlantique Atlantic
504 # C: du Centre Central
505 # E: de l'Est Eastern
506 # M: Mountain
507 # N: Newfoundland
508 # P: du Pacifique Pacific
509 # R: des Rocheuses
510 # T: de Terre-Neuve
511 # Y: du Yukon Yukon
512 #
513 # From Paul Eggert <eggert@twinsun.com> (1994-11-22):
514 # Alas, this sort of thing must be handled by localization software.
516 # The data for Canada are all from Shanks (1991).
519 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
520 Rule Canada 1918 only - Apr 14 2:00 1:00 D
521 Rule Canada 1918 only - Oct 31 2:00 0 S
522 Rule Canada 1942 only - Feb 9 2:00 1:00 D
523 Rule Canada 1945 only - Sep 30 2:00 0 S
524 Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D
525 Rule Canada 1974 max - Oct lastSun 2:00 0 S
526 Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D
529 # Newfoundland
531 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
532 Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D
533 Rule StJohns 1917 only - Sep 17 2:00 0 S
534 Rule StJohns 1918 only - Oct 31 2:00 0 S
535 # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks.
536 Rule StJohns 1919 only - May 5 23:00 1:00 D
537 Rule StJohns 1919 only - Aug 12 23:00 0 S
538 # For 1931-1935 Whitman gives Apr same date; go with Shanks.
539 Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D
540 Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S
541 # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman.
542 Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D
543 Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S
544 # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman.
545 Rule StJohns 1942 only - Mar 1 0:00 1:00 D
546 Rule StJohns 1942 only - Dec 31 0:00 0 S
547 Rule StJohns 1943 only - May 30 0:00 1:00 D
548 Rule StJohns 1943 only - Sep 5 0:00 0 S
549 Rule StJohns 1944 only - Jul 10 0:00 1:00 D
550 Rule StJohns 1944 only - Sep 2 0:00 0 S
551 Rule StJohns 1945 only - Jan 1 0:00 1:00 D
552 Rule StJohns 1945 only - Oct 7 2:00 0 S
553 # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives
554 # Apr 30 - Sep 24; go with Shanks.
555 Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D
556 Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S
557 Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D
558 Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S
559 Rule StJohns 1960 max - Oct lastSun 2:00 0 S
560 Rule StJohns 1987 only - Apr Sun>=1 2:00 1:00 D
561 Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 DD
562 Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D
563 # St John's has an apostrophe, but Posix file names can't have apostrophes.
564 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
565 Zone America/St_Johns -3:30:52 - LMT 1884
566 -3:31 StJohns N%sT 1935 Mar 30
567 -3:30 StJohns N%sT
570 # Labrador, New Brunswick, Nova Scotia, Prince Edward I
572 # From Paul Eggert (1996-06-12):
573 # Shanks writes that since 1970 most of this region has been like Halifax.
574 # Many locales did not observe peacetime DST until 1972;
575 # Glace Bay, NS is the largest that we know of.
576 # Shanks also writes that Liverpool, NS was the only town in Canada to observe
577 # DST in 1971 but not 1970; for now we'll assume this is a typo.
579 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
580 Rule Halifax 1916 only - Apr 1 0:00 1:00 D
581 Rule Halifax 1916 only - Oct 1 0:00 0 S
582 Rule Halifax 1918 only - Apr 14 2:00 1:00 D
583 Rule Halifax 1918 only - Oct 31 2:00 0 S
584 Rule Halifax 1920 only - May 9 0:00 1:00 D
585 Rule Halifax 1920 only - Aug 29 0:00 0 S
586 Rule Halifax 1921 only - May 6 0:00 1:00 D
587 Rule Halifax 1921 1922 - Sep 5 0:00 0 S
588 Rule Halifax 1922 only - Apr 30 0:00 1:00 D
589 Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D
590 Rule Halifax 1923 only - Sep 4 0:00 0 S
591 Rule Halifax 1924 only - Sep 15 0:00 0 S
592 Rule Halifax 1925 only - Sep 28 0:00 0 S
593 Rule Halifax 1926 only - May 16 0:00 1:00 D
594 Rule Halifax 1926 only - Sep 13 0:00 0 S
595 Rule Halifax 1927 only - May 1 0:00 1:00 D
596 Rule Halifax 1927 only - Sep 26 0:00 0 S
597 Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D
598 Rule Halifax 1928 only - Sep 9 0:00 0 S
599 Rule Halifax 1929 only - Sep 3 0:00 0 S
600 Rule Halifax 1930 only - Sep 15 0:00 0 S
601 Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S
602 Rule Halifax 1933 only - Apr 30 0:00 1:00 D
603 Rule Halifax 1933 only - Oct 2 0:00 0 S
604 Rule Halifax 1934 only - May 20 0:00 1:00 D
605 Rule Halifax 1934 only - Sep 16 0:00 0 S
606 Rule Halifax 1935 only - Jun 2 0:00 1:00 D
607 Rule Halifax 1935 only - Sep 30 0:00 0 S
608 Rule Halifax 1936 only - Jun 1 0:00 1:00 D
609 Rule Halifax 1936 only - Sep 14 0:00 0 S
610 Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D
611 Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S
612 Rule Halifax 1939 only - May 28 0:00 1:00 D
613 Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D
614 Rule Halifax 1942 only - Feb 9 2:00 1:00 D
615 Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S
616 Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D
617 Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D
618 Rule Halifax 1962 max - Oct lastSun 2:00 0 S
619 Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D
620 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
621 Zone America/Halifax -4:14:24 - LMT 1902 Jun 15
622 -4:00 Halifax A%sT
623 Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15
624 -4:00 Canada A%sT 1953
625 -4:00 Halifax A%sT 1954
626 -4:00 - AST 1972
627 -4:00 Halifax A%sT
630 # Ontario, Quebec
632 # From Paul Eggert (1996-06-12):
633 # Shanks writes that since 1970 most of this region has been like Montreal.
634 # Thunder Bay skipped DST in 1973.
635 # Many smaller locales did not observe peacetime DST until 1974;
636 # Nipigon (EST) and Rainy River (CST) are the largest that we know of.
637 # Far west Ontario is like Winnipeg; far east Quebec is like Halifax.
639 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
640 Rule Mont 1917 only - Mar 25 2:00 1:00 D
641 Rule Mont 1917 only - Apr 24 0:00 0 S
642 Rule Mont 1918 only - Apr 14 2:00 1:00 D
643 Rule Mont 1918 only - Oct 31 2:00 0 S
644 Rule Mont 1919 only - Mar 31 2:30 1:00 D
645 Rule Mont 1919 only - Oct 25 2:30 0 S
646 Rule Mont 1920 only - May 2 2:30 1:00 D
647 Rule Mont 1920 only - Oct 3 2:30 0 S
648 Rule Mont 1921 only - May 1 2:00 1:00 D
649 Rule Mont 1921 only - Oct 2 2:30 0 S
650 Rule Mont 1922 only - Apr 30 2:00 1:00 D
651 Rule Mont 1922 only - Oct 1 2:30 0 S
652 Rule Mont 1924 only - May 17 2:00 1:00 D
653 Rule Mont 1924 1926 - Sep lastSun 2:30 0 S
654 Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D
655 Rule Mont 1927 only - May 1 0:00 1:00 D
656 Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S
657 Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D
658 Rule Mont 1932 only - May 1 0:00 1:00 D
659 Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D
660 Rule Mont 1933 only - Oct 1 0:00 0 S
661 Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S
662 Rule Mont 1945 1948 - Sep lastSun 2:00 0 S
663 Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D
664 Rule Mont 1949 1950 - Oct lastSun 2:00 0 S
665 Rule Mont 1951 1956 - Sep lastSun 2:00 0 S
666 Rule Mont 1957 max - Oct lastSun 2:00 0 S
667 Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D
668 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
669 Zone America/Montreal -4:54:16 - LMT 1884
670 -5:00 Mont E%sT
671 Zone America/Thunder_Bay -5:57:00 - LMT 1895
672 -5:00 Canada E%sT 1970
673 -5:00 Mont E%sT 1973
674 -5:00 - EST 1974
675 -5:00 Canada E%sT
676 Zone America/Nipigon -5:53:04 - LMT 1895
677 -5:00 Canada E%sT
678 Zone America/Rainy_River -6:17:56 - LMT 1895
679 -6:00 Canada C%sT
682 # Manitoba
684 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
685 Rule Winn 1916 only - Apr 23 0:00 1:00 D
686 Rule Winn 1916 only - Sep 17 0:00 0 S
687 Rule Winn 1918 only - Apr 14 2:00 1:00 D
688 Rule Winn 1918 only - Oct 31 2:00 0 S
689 Rule Winn 1937 only - May 16 2:00 1:00 D
690 Rule Winn 1937 only - Sep 26 2:00 0 S
691 Rule Winn 1942 only - Feb 9 2:00 1:00 D
692 Rule Winn 1945 only - Sep lastSun 2:00 0 S
693 Rule Winn 1946 only - May 12 2:00 1:00 D
694 Rule Winn 1946 only - Oct 13 2:00 0 S
695 Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D
696 Rule Winn 1947 1949 - Sep lastSun 2:00 0 S
697 Rule Winn 1950 only - May 1 2:00 1:00 D
698 Rule Winn 1950 only - Sep 30 2:00 0 S
699 Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D
700 Rule Winn 1951 1958 - Sep lastSun 2:00 0 S
701 Rule Winn 1959 only - Oct lastSun 2:00 0 S
702 Rule Winn 1960 only - Sep lastSun 2:00 0 S
703 Rule Winn 1963 only - Apr lastSun 2:00 1:00 D
704 Rule Winn 1963 only - Sep 22 2:00 0 S
705 Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D
706 Rule Winn 1966 max - Oct lastSun 2:00 0 S
707 Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D
708 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
709 Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16
710 -6:00 Winn C%sT
713 # Saskatchewan
715 # From Paul Eggert (1996-06-12):
716 # Shanks writes that since 1970 most of this region has been like Regina.
717 # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972.
718 # Other western towns (e.g. Lloydminster) are like Edmonton.
720 # From W. Jones <jones@skdad.usask.ca> (November 6, 1992):
721 # The. . .below is based on information I got from our law library, the
722 # provincial archives, and the provincial Community Services department.
723 # A precise history would require digging through newspaper archives, and
724 # since you didn't say what you wanted, I didn't bother.
725 #
726 # Saskatchewan is split by a time zone meridian (105W) and over the years
727 # the boundary became pretty ragged as communities near it reevaluated
728 # their affiliations in one direction or the other. In 1965 a provincial
729 # referendum favoured legislating common time practices.
730 #
731 # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of
732 # Saskatchewan 1978) was proclaimed, and established that the eastern
733 # part of Saskatchewan would use CST year round, that districts in
734 # northwest Saskatchewan would by default follow CST but could opt to
735 # follow Mountain Time rules (thus 1 hour difference in the winter and
736 # zero in the summer), and that districts in southwest Saskatchewan would
737 # by default follow MT but could opt to follow CST.
738 #
739 # It took a few years for the dust to settle (I know one story of a town
740 # on one time zone having its school in another, such that a mom had to
741 # serve her family lunch in two shifts), but presently it seems that only
742 # a few towns on the border with Alberta (e.g. Lloydminster) follow MT
743 # rules any more; all other districts appear to have used CST year round
744 # since sometime in the 1960s.
746 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
747 Rule Regina 1918 only - Apr 14 2:00 1:00 D
748 Rule Regina 1918 only - Oct 31 2:00 0 S
749 Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D
750 Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S
751 Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D
752 Rule Regina 1937 only - Oct Sun>=8 0:00 0 S
753 Rule Regina 1938 only - Oct Sun>=1 0:00 0 S
754 Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S
755 Rule Regina 1942 only - Feb 9 2:00 1:00 D
756 Rule Regina 1945 only - Sep lastSun 2:00 0 S
757 Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D
758 Rule Regina 1946 only - Oct Sun>=8 2:00 0 S
759 Rule Regina 1947 1959 - Apr lastSun 2:00 1:00 D
760 Rule Regina 1947 1958 - Sep lastSun 2:00 0 S
761 Rule Regina 1959 only - Oct lastSun 2:00 0 S
762 #
763 Rule Swift 1957 only - Apr lastSun 2:00 1:00 D
764 Rule Swift 1957 only - Oct lastSun 2:00 0 S
765 Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D
766 Rule Swift 1959 only - Oct lastSun 2:00 0 S
767 Rule Swift 1960 1961 - Sep lastSun 2:00 0 S
768 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
769 Zone America/Regina -6:58:36 - LMT 1905 Sep
770 -7:00 Regina M%sT 1960 Apr lastSun 2:00
771 -6:00 - CST
772 Zone America/Swift_Current -7:11:20 - LMT 1905 Sep
773 -7:00 Canada M%sT 1946 Apr lastSun 2:00
774 -7:00 Regina M%sT 1950
775 -7:00 Swift M%sT 1972 Apr lastSun 2:00
776 -6:00 - CST
779 # Alberta
781 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
782 Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D
783 Rule Edm 1918 only - Oct 31 2:00 0 S
784 Rule Edm 1919 only - May 27 2:00 0 S
785 Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D
786 Rule Edm 1920 only - Oct lastSun 2:00 0 S
787 Rule Edm 1921 1923 - Sep lastSun 2:00 0 S
788 Rule Edm 1942 only - Feb 9 2:00 1:00 D
789 Rule Edm 1945 only - Sep lastSun 2:00 0 S
790 Rule Edm 1947 only - Apr lastSun 2:00 1:00 D
791 Rule Edm 1947 only - Sep lastSun 2:00 0 S
792 Rule Edm 1967 only - Apr lastSun 2:00 1:00 D
793 Rule Edm 1967 only - Oct lastSun 2:00 0 S
794 Rule Edm 1969 only - Apr lastSun 2:00 1:00 D
795 Rule Edm 1969 only - Oct lastSun 2:00 0 S
796 Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D
797 Rule Edm 1972 max - Oct lastSun 2:00 0 S
798 Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D
799 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
800 Zone America/Edmonton -7:33:52 - LMT 1906 Sep
801 -7:00 Edm M%sT
804 # British Columbia
806 # From Paul Eggert (1996-06-12):
807 # Shanks writes that since 1970 most of this region has been like Vancouver.
808 # Dawswon Creek uses MST. Much of east BC is like Edmonton.
810 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
811 Rule Vanc 1918 only - Apr 14 2:00 1:00 D
812 Rule Vanc 1918 only - Oct 31 2:00 0 S
813 Rule Vanc 1942 only - Feb 9 2:00 1:00 D
814 Rule Vanc 1945 only - Sep 30 2:00 0 S
815 Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D
816 Rule Vanc 1946 only - Oct 13 2:00 0 S
817 Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S
818 Rule Vanc 1962 max - Oct lastSun 2:00 0 S
819 Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D
820 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
821 Zone America/Vancouver -8:12:28 - LMT 1884
822 -8:00 Vanc P%sT
823 Zone America/Dawson_Creek -8:00:56 - LMT 1884
824 -8:00 Canada P%sT 1947
825 -8:00 Vanc P%sT 1972 Aug 30 2:00
826 -7:00 - MST
829 # Northwest Territories, Yukon
831 # From Paul Eggert (1996-06-12):
832 # Dawson switched to PST in 1973. Inuvik switched to MST in 1979.
833 # Shanks's table for Watson Lake is corrupted, so we have no data there.
835 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
836 Rule NT_YK 1918 only - Apr 14 2:00 1:00 D
837 Rule NT_YK 1918 only - Oct 27 2:00 0 S
838 Rule NT_YK 1919 only - May 25 2:00 1:00 D
839 Rule NT_YK 1919 only - Nov 1 0:00 0 S
840 Rule NT_YK 1942 only - Feb 9 2:00 1:00 D
841 Rule NT_YK 1945 only - Sep 30 2:00 0 S
842 # 0:00 ??
843 Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD
844 Rule NT_YK 1965 only - Oct lastSun 2:00 0 S
845 Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D
846 Rule NT_YK 1980 max - Oct lastSun 2:00 0 S
847 Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D
848 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
849 Zone America/Pangnirtung -4:22:56 - LMT 1884
850 -4:00 NT_YK A%sT
851 Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay
852 -5:00 NT_YK E%sT
853 Zone America/Rankin_Inlet -6:08:40 - LMT 1884
854 -6:00 NT_YK C%sT
855 Zone America/Yellowknife -7:37:24 - LMT 1884
856 -7:00 NT_YK M%sT
857 Zone America/Inuvik -8:54:00 - LMT 1884
858 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00
859 -7:00 NT_YK M%sT
860 Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20
861 -9:00 NT_YK Y%sT 1966 Jul 1 2:00
862 -8:00 NT_YK P%sT
863 Zone America/Dawson -9:17:40 - LMT 1900 Aug 20
864 -9:00 NT_YK Y%sT 1973 Oct lastSun 2:00
865 -8:00 NT_YK P%sT
868 ###############################################################################
870 # Mexico
872 # From Guy Harris:
873 # Rules are from the Official Airline Guide, Worldwide Edition, for 1987.
874 # Rules prior to 1987 are unknown.
875 # The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana
876 # observe DST." This is presumably Baja California Norte, above 28th parallel,
877 # as listed there; [there is also] "Baja California Sur and N. Pacific
878 # Coast (States of Sinaloa and Sonora)."
880 # From Bob Devine (January 28, 1988):
881 # The Federal District (where Mexico City is) has observed [DST] several
882 # times but not recently.
883 #
884 # I don't where to drawn the line in the North Baja area. 28th latitude
885 # sounds good -- but it may be higher (how far [d]o radio stations from
886 # San Diego affect culture?).
887 #
888 # The dates of DST probably go back to 1981. The rules are the same as
889 # US's. This is going to be a headache for US presidential electi[o]n years!
891 # From Arthur David Olson (February 13, 1988)
892 # Since the 1981 starting date is only "probable," we'll keep the 1987
893 # starting date below.
895 # From U. S. Naval Observatory (January 19, 1989):
896 # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND
897 # MEXICO BAJA CAL N N. PACIFIC COAST (STATES
898 # MEXICO BAJA CAL N OF SINALOA AND SONORA)
899 # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
900 # MEXICO BAJA CAL N - OCT 29
901 # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3
902 # MEXICO BAJA CAL N - 0CT 29
903 # MEXICO 6 H BEHIND UTC STATES OF DURANGO,
904 # MEXICO COAHUILA, NUEVO LEON,
905 # MEXICO TAMAULIPAS
906 # MEXICO 5 H BEHIND UTC STATES OF DURANGO,
907 # MEXICO COAHUILA, NUEVO LEON,
908 # MEXICO TAMAULIPAS APR 3 - OCT 29
909 # MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF
910 # MEXICO CAMPECHE, QUINTANA ROO AND
911 # MEXICO YUCATAN
913 # From Arthur David Olson (January 21, 1989):
914 # April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem.
915 # USNO claims there should be four Mexican zones rather than three:
916 # a zone that's GMT-8 with DST; a zone that's always GMT-7;
917 # a zone that's GMT-6 with DST; and a zone that's always GMT-6.
919 # From Paul Eggert <eggert@twinsun.com> (1993-11-18):
920 # Shanks also says there are four zones, but disagrees about the fourth.
921 # Instead of GMT-6 with DST, he says there's GMT-8 without DST.
923 # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15):
924 # A guy from our Mexico subsidiary finally found the Presidential Decree
925 # outlining the timezone changes in Mexico.
926 #
927 # ------------- Begin Forwarded Message -------------
928 #
929 # I finally got my hands on the Official Presidential Decree that sets up the
930 # rules for the DST changes. The rules are:
931 #
932 # 1. The country is divided in 3 timezones:
933 # - Baja California Norte (the Mexico/BajaNorte TZ)
934 # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ)
935 # - The rest of the country (the Mexico/General TZ)
936 #
937 # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October
938 # at 2:00 AM, the times in each zone are as follows:
939 # BajaNorte: GMT+7
940 # BajaSur: GMT+6
941 # General: GMT+5
942 #
943 # 3. The rest of the year, the times are as follows:
944 # BajaNorte: GMT+8
945 # BajaSur: GMT+7
946 # General: GMT+6
947 #
948 # The Decree was published in Mexico's Official Newspaper on January 4th.
949 #
950 # -------------- End Forwarded Message --------------
951 # From Paul Eggert (1996-06-12):
952 # For an English translation of the decree,
953 # see ``Diario Oficial: Time Zone Changeover'',
954 # <URL:http://mexico-travel.com/extra/timezone_eng.html> (1996-01-04).
956 # From Shanks (1991):
957 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
958 Rule Mexico 1939 only - Feb 5 0:00 1:00 D
959 Rule Mexico 1939 only - Jun 25 0:00 0 S
960 Rule Mexico 1940 only - Dec 9 0:00 1:00 D
961 Rule Mexico 1941 only - Apr 1 0:00 0 S
962 Rule Mexico 1943 only - Dec 16 0:00 1:00 D
963 Rule Mexico 1944 only - May 1 0:00 0 S
964 Rule Mexico 1950 only - Feb 12 0:00 1:00 D
965 Rule Mexico 1950 only - Jul 30 0:00 0 S
966 Rule Mexico 1996 max - Apr Sun>=1 2:00 1:00 D
967 Rule Mexico 1996 max - Oct lastSun 2:00 0 S
968 #
969 Rule BajaN 1950 1966 - Apr lastSun 2:00 1:00 D
970 Rule BajaN 1950 1961 - Sep lastSun 2:00 0 S
971 Rule BajaN 1961 1966 - Oct lastSun 2:00 0 S
972 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
973 Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24
974 -7:00 - MST 1927 Jun 10 23:00
975 -6:00 - CST 1930 Nov 15
976 -7:00 - MST 1931 May 1 23:00
977 -6:00 - CST 1931 Oct
978 -7:00 - MST 1932 Mar 30 23:00
979 -6:00 Mexico C%sT
980 Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20
981 -7:00 - MST 1927 Jun 10 23:00
982 -6:00 - CST 1930 Nov 15
983 -7:00 - MST 1931 May 1 23:00
984 -6:00 - CST 1931 Oct
985 -7:00 - MST 1932 Mar 30 23:00
986 -6:00 - CST 1942 Apr
987 -7:00 - MST 1949 Jan 14
988 -8:00 - PST 1970
989 -7:00 Mexico M%sT
990 Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56
991 -8:00 - PST 1927 Jun 10 23:00
992 -7:00 - MST 1930 Nov 16
993 -8:00 - PST 1942 Apr
994 -7:00 - MST 1949 Jan 14
995 -8:00 BajaN P%sT 1967 Apr lastSun 2:00
996 -8:00 US P%sT 1996
997 -8:00 Mexico P%sT
998 Zone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32
999 -8:00 - PST 1927 Jun 10 23:00
1000 -7:00 - MST 1930 Nov 16
1001 -8:00 - PST 1942 Apr
1002 -7:00 - MST 1949 Jan 14
1003 -8:00 - PST 1996
1004 -8:00 Mexico P%sT
1005 #
1006 # Revillagigedo Is
1007 # no information
1009 ###############################################################################
1011 # Anguilla
1012 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1013 Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2
1014 -4:00 - AST
1016 # Antigua and Barbuda
1017 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1018 Zone America/Antigua -4:07:12 - LMT 1912 Mar 2
1019 -5:00 - EST 1951
1020 -4:00 - AST
1022 # Bahamas
1023 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1024 Rule Bahamas 1964 max - Oct lastSun 2:00 0 S
1025 Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D
1026 Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D
1027 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1028 Zone America/Nassau -5:09:24 - LMT 1912 Mar 2
1029 -5:00 Bahamas E%sT
1031 # Barbados
1032 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1033 Rule Barb 1977 only - Jun 12 2:00 1:00 D
1034 Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S
1035 Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D
1036 Rule Barb 1979 only - Sep 30 2:00 0 S
1037 Rule Barb 1980 only - Sep 25 2:00 0 S
1038 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1039 Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown
1040 -3:58 - BMT 1932 # Bridgetown Mean Time
1041 -4:00 Barb A%sT
1043 # Belize
1044 # Whitman entirely disagrees with Shanks; go with Shanks.
1045 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1046 Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD
1047 Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S
1048 Rule Belize 1973 only - Dec 5 0:00 1:00 D
1049 Rule Belize 1974 only - Feb 9 0:00 0 S
1050 Rule Belize 1982 only - Dec 18 0:00 1:00 D
1051 Rule Belize 1983 only - Feb 12 0:00 0 S
1052 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1053 Zone America/Belize -5:52:48 - LMT 1912 Apr
1054 -6:00 Belize C%sT
1056 # Bermuda
1057 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1058 Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton
1059 -4:00 - AST 1974 Apr 28 2:00
1060 -4:00 Bahamas A%sT
1062 # Cayman Is
1063 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1064 Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown
1065 -5:07 - KMT 1912 Feb # Kingston Mean Time
1066 -5:00 - EST
1068 # Clipperton
1069 # uninhabited
1071 # Costa Rica
1072 # Shanks gives some very odd dates for 1991, and stops there.
1073 # For now, we won't guess further.
1074 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1075 Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D
1076 Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S
1077 Rule CR 1991 only - Jan 19 0:00 1:00 D
1078 Rule CR 1991 only - Jul 1 0:00 0 S
1079 # There are too many San Joses elsewhere, so we'll use `Costa Rica'.
1080 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1081 Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose
1082 -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time
1083 -6:00 CR C%sT
1084 # Coco
1085 # no information; probably like America/Costa_Rica
1087 # Cuba
1089 # From Bob Devine (January 28, 1988):
1090 # . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981.
1091 # Change at midnight. In 1979 & 1980, started at 3rd Sunday in March
1092 # (I think).
1094 # From U. S. Naval Observatory (January 19, 1989):
1095 # CUBA 5 H BEHIND UTC
1096 # CUBA 4 H BEHIND UTC MAR 20 - OCT 8
1098 # From Shanks (1991):
1099 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1100 Rule Cuba 1928 only - Jun 10 0:00 1:00 D
1101 Rule Cuba 1928 only - Oct 10 0:00 0 S
1102 Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D
1103 Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S
1104 Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D
1105 Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S
1106 Rule Cuba 1965 only - Jun 1 0:00 1:00 D
1107 Rule Cuba 1965 only - Sep 30 0:00 0 S
1108 Rule Cuba 1966 only - May 29 0:00 1:00 D
1109 Rule Cuba 1966 only - Oct 2 0:00 0 S
1110 Rule Cuba 1967 only - Apr 8 0:00 1:00 D
1111 Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S
1112 Rule Cuba 1968 only - Apr 14 0:00 1:00 D
1113 Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D
1114 Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S
1115 Rule Cuba 1972 1974 - Oct 8 0:00 0 S
1116 Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S
1117 Rule Cuba 1978 only - May 7 0:00 1:00 D
1118 Rule Cuba 1978 1980 - Oct Sun>=8 0:00 0 S
1119 Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D
1120 Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D
1121 Rule Cuba 1981 max - Oct Sun>=8 0:00 0 S
1122 Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D
1123 Rule Cuba 1990 only - Apr 1 0:00 1:00 D
1124 Rule Cuba 1991 max - Mar Sun>=14 0:00 1:00 D
1126 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1127 Zone America/Havana -5:29:28 - LMT 1890
1128 -5:30 - HMT 1925 Jul 19 12:00 # Havana MT
1129 -5:00 Cuba C%sT
1131 # Dominica
1132 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1133 Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau
1134 -4:00 - AST
1136 # Dominican Republic
1137 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1138 Rule DR 1966 only - Oct 30 0:00 1:00 D
1139 Rule DR 1967 only - Feb 28 0:00 0 S
1140 Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD
1141 Rule DR 1970 only - Feb 21 0:00 0 S
1142 Rule DR 1971 only - Jan 20 0:00 0 S
1143 Rule DR 1972 1974 - Jan 21 0:00 0 S
1144 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1145 Zone America/Santo_Domingo -4:39:36 - LMT 1890
1146 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT
1147 -5:00 DR E%sT 1974 Oct 27
1148 -4:00 - AST
1150 # El Salvador
1151 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1152 Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D
1153 Rule Salv 1987 1988 - Sep lastSun 0:00 0 S
1154 # There are too many San Salvadors elsewhere, so we'll use `El Salvador'.
1155 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1156 Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador
1157 -6:00 Salv C%sT
1159 # Grenada
1160 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1161 Zone America/Grenada -4:07:00 - LMT 1911 Jul
1162 -4:00 - AST
1164 # Guadeloupe
1165 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1166 Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre
1167 -4:00 - AST
1169 # Guatemala
1170 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1171 Rule Guat 1973 only - Nov 25 0:00 1:00 D
1172 Rule Guat 1974 only - Feb 24 0:00 0 S
1173 Rule Guat 1983 only - May 21 0:00 1:00 D
1174 Rule Guat 1983 only - Sep 22 0:00 0 S
1175 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1176 Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5
1177 -6:00 Guat C%sT
1179 # Haiti
1180 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1181 Rule Haiti 1983 only - May 8 0:00 1:00 D
1182 Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D
1183 Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S
1184 Rule Haiti 1988 max - Apr Sun>=1 2:00 1:00 D
1185 Rule Haiti 1988 max - Oct lastSun 2:00 0 S
1186 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1187 Zone America/Port-au-Prince -4:49:20 - LMT 1890
1188 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT
1189 -5:00 Haiti E%sT
1191 # Honduras
1192 # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1.
1193 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1194 Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr
1195 -6:00 Salv C%sT
1197 # Jamaica
1199 # From Bob Devine (January 28, 1988):
1200 # Follows US rules.
1202 # From U. S. Naval Observatory (January 19, 1989):
1203 # JAMAICA 5 H BEHIND UTC
1205 # From Shanks (1991):
1206 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1207 Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston
1208 -5:07 - KMT 1912 Feb # Kingston Mean Time
1209 -5:00 - EST 1974 Jan 6 2:00
1210 -5:00 US E%sT
1212 # Martinique
1213 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1214 Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France
1215 -4:04 - FFMT 1911 May # Fort-de-France MT
1216 -4:00 - AST 1980 Apr 6
1217 -4:00 1:00 ADT 1980 Sep 28
1218 -4:00 - AST
1220 # Montserrat
1221 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1222 Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Plymouth
1223 -4:00 - AST
1225 # Nicaragua
1226 # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
1227 Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D
1228 Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S
1229 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1230 Zone America/Managua -5:45:08 - LMT 1890
1231 -5:45 - MMT 1934 Jun 23 # Managua Mean Time
1232 -6:00 - CST 1973 May
1233 -5:00 - EST 1975 Feb 16
1234 -6:00 Nic C%sT
1236 # Panama
1237 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1238 Zone America/Panama -5:18:08 - LMT 1890
1239 -5:20 - PMT 1908 Apr 22 # Panama Mean Time
1240 -5:00 - EST
1242 # Puerto Rico
1243 # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'.
1244 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1245 Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan
1246 -4:00 - AST 1942 May 3
1247 -4:00 1:00 AWT 1945 Sep 30 2:00
1248 -4:00 - AST
1250 # St Kitts-Nevis
1251 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1252 Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre
1253 -4:00 - AST
1255 # St Lucia
1256 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1257 Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries
1258 -4:04 - CMT 1912 # Castries Mean Time
1259 -4:00 - AST
1261 # St Pierre and Miquelon
1262 # There are too many St Pierres elsewhere, so we'll use `Miquelon'.
1263 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1264 Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre
1265 -4:00 - AST 1980 May
1266 -3:00 Mont SP%sT
1268 # St Vincent and the Grenadines
1269 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1270 Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown
1271 -4:05 - KMT 1912 # Kingstown Mean Time
1272 -4:00 - AST
1274 # Turks and Caicos
1275 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1276 Zone America/Grand_Turk -4:44:32 - LMT 1890
1277 -5:07 - KMT 1912 Feb # Kingston Mean Time
1278 -5:00 - EST 1979 Apr 29 2:00
1279 -5:00 US E%sT
1281 # British Virgin Is
1282 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1283 Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town
1284 -4:00 - AST
1286 # Virgin Is
1287 # Zone NAME GMTOFF RULES FORMAT [UNTIL]
1288 Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie
1289 -4:00 - AST