c0dbee2000-08-01Mirar (Pontus Hagland) # @(#)northamerica 7.51 # also includes Central America and the Caribbean # This data is by no means authoritative; if you think you know better, # go ahead and edit the file (and please send any changes to # tz@elsie.nci.nih.gov for general use in the future). # From Paul Eggert <eggert@twinsun.com> (1999-03-22): # A reliable and entertaining source about time zones is # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997). ############################################################################### # United States # From Paul Eggert (1999-03-31): # Howse writes (pp 121-125) that time zones were invented by # Professor Charles Ferdinand Dowd (1825-1904), # Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY). # His pamphlet ``A System of National Time for Railroads'' (1870) # was the result of his proposals at the Convention of Railroad Trunk Lines # in New York City (1869-10). His 1870 proposal was based on Washington, DC, # but in 1872-05 he moved the proposed origin to Greenwich. # His proposal was adopted by the railroads on 1883-11-18 at 12:00, # and the most of the country soon followed suit. # From Paul Eggert <eggert@twinsun.com> (1995-12-19): # A good source for time zone historical data in the US is # Thomas G. Shanks, The American Atlas (5th edition), # San Diego: ACS Publications, Inc. (1991). # Make sure you have the errata sheet; the book is somewhat useless without it. # It is the source for the US and Puerto Rico entries below. # From Paul Eggert (1996-06-12): # Daylight Saving Time was first suggested as a joke by Benjamin Franklin # in his whimsical essay ``Turkey vs Eagle, McCauley is my Beagle'' (1784). # Not everyone is happy with the results: # # I don't really care how time is reckoned so long as there is some # agreement about it, but I object to being told that I am saving # daylight when my reason tells me that I am doing nothing of the kind. # I even object to the implication that I am wasting something # valuable if I stay in bed after the sun has risen. As an admirer # of moonlight I resent the bossy insistence of those who want to # reduce my time for enjoying it. At the back of the Daylight Saving # scheme I detect the bony, blue-fingered hand of Puritanism, eager # to push people into bed earlier, and get them up earlier, to make # them healthy, wealthy and wise in spite of themselves. # # -- Robertson Davies, The Diary of Samuel Marchbanks (1947), XIX, Sunday # From Arthur David Olson: # US Daylight Saving Time ended on the last Sunday of *October* in 1974. # See, for example, the front page of the Saturday, 1974-10-26 # and Sunday, 1974-10-27 editions of the Washington Post. # From Arthur David Olson: # Before the Uniform Time Act of 1966 took effect in 1967, observance of # Daylight Saving Time in the US was by local option, except during wartime. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule US 1918 1919 - Mar lastSun 2:00 1:00 W # War Rule US 1918 1919 - Oct lastSun 2:00 0 S Rule US 1942 only - Feb 9 2:00 1:00 W # War Rule US 1945 only - Sep 30 2:00 0 S Rule US 1967 max - Oct lastSun 2:00 0 S Rule US 1967 1973 - Apr lastSun 2:00 1:00 D Rule US 1974 only - Jan 6 2:00 1:00 D Rule US 1975 only - Feb 23 2:00 1:00 D Rule US 1976 1986 - Apr lastSun 2:00 1:00 D Rule US 1987 max - Apr Sun>=1 2:00 1:00 D # <a href="http://thomas.loc.gov/cgi-bin/bdquery/z?d106:h.r.00177:"> # H.R.177 # </a> (introduced 1999-01-06) would change April to March in the above rule. # From Bob Devine (1988-01-28): # ...Alaska (and Hawaii) had the timezone names changed in 1967. # old new # Pacific Standard Time(PST) -same- # Yukon Standard Time(YST) -same- # Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST) # Nome Standard Time (NT) Bering Standard Time (BST) # # ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz. # The YST zone now covers nearly all of the state, AHST just part # of the Aleutian islands. No DST. # From Paul Eggert (1995-12-19): # The tables below use `NST', not `NT', for Nome Standard Time. # I invented `CAWT' for Central Alaska War Time. # From U. S. Naval Observatory (1989-01-19): # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30 # USA MOUNTAIN 7 H BEHIND UTC DENVER # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST) # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT) # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W # USA - " - 9 H BEHIND UTC APR 3 - OCT 30 # USA HAWAII 10 H BEHIND UTC # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY # From Arthur David Olson (1989-01-21): # The above dates are for 1988. # Note the "AKST" and "AKDT" abbreviations, the claim that there's # no DST in Samoa, and the claim that there is DST in Alaska and the # Aleutians. # From Arthur David Olson (1988-02-13): # Legal standard time zone names, from United States Code (1982 Edition and # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966 # took effect), as explained in sections 263 and 261: # (none) # United States standard eastern time # United States standard mountain time # United States standard central time # United States standard Pacific time # (none) # United States standard Alaska time # (none) # Next, names from 1967-04-01 until 1983-11-30 (the date for # public law 98-181): # Atlantic standard time # eastern standard time # central standard time # mountain standard time # Pacific standard time # Yukon standard time # Alaska-Hawaii standard time # Bering standard time # And after 1983-11-30: # Atlantic standard time # eastern standard time # central standard time # mountain standard time # Pacific standard time # Alaska standard time # Hawaii-Aleutian standard time # Samoa standard time # The law doesn't give abbreviations. # # From Paul Eggert (1995-12-19): # Shanks uses 1983-10-30, not 1983-11-30, for the 1983 transitions. # Go with Shanks. # US Eastern time, represented by New York # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule NYC 1920 only - Mar lastSun 2:00 1:00 D Rule NYC 1920 only - Oct lastSun 2:00 0 S Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D Rule NYC 1921 1954 - Sep lastSun 2:00 0 S Rule NYC 1955 1966 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/New_York -4:56:02 - LMT 1883 Nov 18 12:00 -5:00 US E%sT 1920 -5:00 NYC E%sT 1942 -5:00 US E%sT 1946 -5:00 NYC E%sT 1967 -5:00 US E%sT # US Central time, represented by Chicago # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Chicago 1920 only - Jun 13 2:00 1:00 D Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1920 -6:00 Chicago C%sT 1936 Mar 1 2:00 -5:00 - EST 1936 Nov 15 2:00 -6:00 Chicago C%sT 1942 -6:00 US C%sT 1946 -6:00 Chicago C%sT 1967 -6:00 US C%sT # US Mountain time, represented by Denver # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D Rule Denver 1920 only - Oct lastSun 2:00 0 S Rule Denver 1921 only - May 22 2:00 0 S Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D Rule Denver 1965 1966 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Denver -6:59:56 - LMT 1883 Nov 18 12:00 -7:00 US M%sT 1920 -7:00 Denver M%sT 1942 -7:00 US M%sT 1946 -7:00 Denver M%sT 1967 -7:00 US M%sT # US Pacific time, represented by Los Angeles # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule CA 1948 only - Mar 14 2:00 1:00 D Rule CA 1949 only - Jan 1 2:00 0 S Rule CA 1950 1966 - Apr lastSun 2:00 1:00 D Rule CA 1950 1961 - Sep lastSun 2:00 0 S Rule CA 1962 1966 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 12:00 -8:00 US P%sT 1946 -8:00 CA P%sT 1967 -8:00 US P%sT # Alaska # AK%sT is the modern abbreviation for -9:00 per USNO. # # From Paul Eggert (1995-12-19): # Howse writes that Alaska switched from the Julian to the Gregorian calendar, # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia. # This was on 1867-10-18. We omit this transition, since we can't represent # changes from Julian to Gregorian. # # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Juneau -8:57:41 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 -8:00 - PST 1969 -8:00 US P%sT 1983 Oct 30 2:00 -9:00 US AK%sT Zone America/Yakutat -9:18:55 - LMT 1900 Aug 20 12:00 -9:00 - YST 1942 -9:00 US Y%sT 1946 -9:00 - YST 1969 -9:00 US Y%sT 1983 Oct 30 2:00 -9:00 US AK%sT Zone America/Anchorage -9:59:36 - LMT 1900 Aug 20 12:00 -10:00 - CAT 1942 -10:00 US CAT/CAWT 1946 -10:00 - CAT 1967 Apr -10:00 - AHST 1969 -10:00 US AH%sT 1983 Oct 30 2:00 -9:00 US AK%sT Zone America/Nome -11:01:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 -11:00 - NST 1967 Apr -11:00 - BST 1969 -11:00 US B%sT 1983 Oct 30 2:00 -9:00 US AK%sT Zone America/Adak -11:46:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 -11:00 - NST 1967 Apr -11:00 - BST 1969 -11:00 US B%sT 1983 Oct 30 2:00 -10:00 US HA%sT # Shanks writes that part of southwest Alaska (e.g. Aniak) # switched from -11:00 to -10:00 on 1968-09-22 at 02:00, # and another part (e.g. Akiak) made the same switch five weeks later. # These switches don't quite make our 1970 cutoff. # Hawaii # # From Arthur David Olson: # And then there's Hawaii. # DST was observed for one day in 1933; # standard time was changed by half an hour in 1947; # it's always standard as of 1986. # # From Paul Eggert: # Shanks says the 1933 experiment lasted for three weeks. Go with Shanks. # Zone Pacific/Honolulu -10:31:26 - LMT 1900 Jan 1 12:00 -10:30 - HST 1933 Apr 30 2:00 -10:30 1:00 HDT 1933 May 21 2:00 -10:30 US H%sT 1947 Jun 8 2:00 -10:00 - HST # Now we turn to US areas that have diverged from the consensus since 1970. # Arizona mostly uses MST. Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 12:00 -7:00 US M%sT 1944 Jan 1 00:01 -7:00 - MST 1944 Mar 17 00:01 -7:00 US M%sT 1944 Oct 1 00:01 -7:00 - MST 1967 -7:00 US M%sT 1968 -7:00 - MST # From Arthur David Olson (1988-02-13): # A writer from the Inter Tribal Council of Arizona, Inc., # notes in private correspondence dated 12/28/87 that "Presently, only the # Navajo Nation participates in the Daylight Saving Time policy, due to its # large size and location in three states." (The "only" means that other # tribal nations don't use DST.) Link America/Denver America/Shiprock # Southern Idaho and eastern Oregon switched four weeks late in 1974. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Boise -7:44:49 - LMT 1883 Nov 18 12:00 -8:00 US P%sT 1923 May 13 2:00 -7:00 US M%sT 1974 -7:00 - MST 1974 Feb 3 2:00 -7:00 US M%sT # Indiana # # For a map of Indiana's time zone regions, see: # <a href="http://www.mccsc.edu/time.html"> # What time is it in Indiana? # </a> (1999-04-06) # # From Paul Eggert (1995-12-19): # Indiana generally observes either EST all year, or CST/CDT, # but areas near Cincinnati and Louisville use those cities' timekeeping # and in 1969 and 1970 the whole state observed daylight time; # and there are other exceptions as noted below. # Shanks partitions Indiana into 345 regions, each with its own time history, # and writes ``Even newspaper reports present contradictory information.'' # Fortunately, most of the complexity occurred before our cutoff date of 1970. # # Since 1970, EST-only Indiana has been like America/Indianapolis, # with exceptions noted below for Crawford, Starke, and Switzerland counties. # The parts of Indiana not listed below have been like America/Chicago, # America/Louisville, or America/New_York. # # Other than Indianapolis, the Indiana place names are so nondescript # that they would be ambiguous if we left them at the `America' level. # So we reluctantly put them all in a subdirectory `America/Indiana'. # # Most of EST-only Indiana last observed DST in 1970. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Indianapolis -5:44:38 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1920 -6:00 Indianapolis C%sT 1942 -6:00 US C%sT 1946 -6:00 Indianapolis C%sT 1955 Apr 24 2:00 -5:00 - EST 1957 Sep 29 2:00 -6:00 - CST 1958 Apr 27 2:00 -5:00 - EST 1969 -5:00 US E%sT 1971 -5:00 - EST Link America/Indianapolis America/Indiana/Indianapolis # # Part of Crawford County, Indiana, last observed DST in 1975, # and left its clocks alone in 1974. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D Rule Marengo 1951 only - Sep lastSun 2:00 0 S Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1951 -6:00 Marengo C%sT 1961 Apr 30 2:00 -5:00 - EST 1969 -5:00 US E%sT 1974 Jan 6 2:00 -6:00 1:00 CDT 1974 Oct 27 2:00 -5:00 US E%sT 1976 -5:00 - EST # # Starke County, Indiana # From Arthur David Olson (1991-10-28): # An article on page A3 of the Sunday, 1991-10-27 Washington Post # notes that Starke County switched from Central time to Eastern time as of # 1991-10-27. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D Rule Starke 1947 1954 - Sep lastSun 2:00 0 S Rule Starke 1955 1956 - Oct lastSun 2:00 0 S Rule Starke 1957 1958 - Sep lastSun 2:00 0 S Rule Starke 1959 1961 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1947 -6:00 Starke C%sT 1962 Apr 29 2:00 -5:00 - EST 1963 Oct 27 2:00 -6:00 US C%sT 1991 Oct 27 2:00 -5:00 - EST # # Switzerland County, Indiana, last observed DST in 1972. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1954 Apr 25 2:00 -5:00 - EST 1969 -5:00 US E%sT 1973 -5:00 - EST # Part of Kentucky left its clocks alone in 1974. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Louisville 1921 only - May 1 2:00 1:00 D Rule Louisville 1921 only - Sep 1 2:00 0 S Rule Louisville 1941 1961 - Apr lastSun 2:00 1:00 D Rule Louisville 1941 only - Sep lastSun 2:00 0 S Rule Louisville 1946 only - Jun 2 2:00 0 S Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S Rule Louisville 1956 1960 - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Louisville -5:43:02 - LMT 1883 Nov 18 12:00 -6:00 US C%sT 1921 -6:00 Louisville C%sT 1942 -6:00 US C%sT 1946 -6:00 Louisville C%sT 1961 Jul 23 2:00 -5:00 - EST 1968 -5:00 US E%sT 1974 Jan 6 2:00 -6:00 1:00 CDT 1974 Oct 27 2:00 -5:00 US E%sT # Wayne, Clinton, and Russell Counties, Kentucky # From # <a href="http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=1999_register&docid=99-26945-filed"> # Federal Register Doc. 99-26945 # </a> (1999-10-14 08:45-04) # In response to a petition by the Wayne County, Kentucky, Fiscal Court, # the Department of Transportation (DOT) proposed to move Wayne County, # Kentucky, from the Central Time Zone to the Eastern Time Zone.... Now # the earliest date that the proposed change might take effect is # October 29, 2000. # # From # <a href="http://www.lake-cumberland.com/life/archive/news990129time.shtml"> # Lake Cumberland LIFE # </a> (1999-01-29) via WKYM-101.7: # Clinton County has joined Wayne County in asking the DoT to change from # the Central to the Eastern time zone.... The Wayne County government made # the same request in December. And while Russell County officials have not # taken action, the majority of respondents to a poll conducted there in # August indicated they would like to change to "fast time" also. # The three Lake Cumberland counties are the farthest east of any U.S. # location in the Central time zone. # Michigan # # From Bob Devine (1988-01-28): # Michigan didn't observe DST from 1968 to 1973. # # From Paul Eggert (1999-03-31): # Shanks writes that Michigan started using standard time on 1885-09-18, # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01) # that Detroit kept # # local time until 1900 when the City Council decreed that clocks should # be put back twenty-eight minutes to Central Standard Time. Half the # city obeyed, half refused. After considerable debate, the decision # was rescinded and the city reverted to Sun time. A derisive offer to # erect a sundial in front of the city hall was referred to the # Committee on Sewers. Then, in 1905, Central time was adopted # by city vote. # # This story is too entertaining to be false, so go with Howse over Shanks. # # Most of Michigan observed DST from 1973 on, but was a bit late in 1975. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D Rule Detroit 1948 only - Sep lastSun 2:00 0 S Rule Detroit 1967 only - Jun 14 2:00 1:00 D Rule Detroit 1967 only - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Detroit -5:32:11 - LMT 1905 -6:00 - CST 1915 May 15 2:00 -5:00 - EST 1942 -5:00 US E%sT 1946 -5:00 Detroit E%sT 1973 -5:00 US E%sT 1975 -5:00 - EST 1975 Apr 27 2:00 -5:00 US E%sT # # The Michigan border with Wisconsin switched from EST to CST/CDT in 1973. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D Rule Menominee 1946 only - Sep lastSun 2:00 0 S Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D Rule Menominee 1966 only - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00 -6:00 US C%sT 1946 -6:00 Menominee C%sT 1969 Apr 27 2:00 -5:00 - EST 1973 Apr 29 2:00 -6:00 US C%sT # Navassa # claimed by US under the provisions of the 1856 Guano Islands Act # also claimed by Haiti # occupied 1857/1900 by the Navassa Phosphate Co # US lighthouse 1917/1997-01 # currently uninhabited # see Mark Fineman, ``An Isle Rich in Guano and Discord'', # _Los Angeles Times_ (1998-11-10), A1, A10; it cites # Jimmy Skaggs, _The Great Guano Rush_ (1994). # Old names, for S5 users # Link LINK-FROM LINK-TO Link America/New_York EST5EDT Link America/Chicago CST6CDT Link America/Denver MST7MDT Link America/Los_Angeles PST8PDT Link America/Indianapolis EST Link America/Phoenix MST Link Pacific/Honolulu HST ################################################################################ # From Paul Eggert <eggert@twinsun.com> (1999-10-29): # A good source for time zone historical data outside the US is # Thomas G. Shanks, The International Atlas (5th edition), # San Diego: ACS Publications, Inc. (1999). # # Gwillim Law <Gwil_Law@bridge-point.com> writes that a good source # for recent time zone data is the International Air Transport # Association's Standard Schedules Information Manual (IATA SSIM), # published semiannually. Law sent in several helpful summaries # of the IATA's data after 1990. # # Except where otherwise noted, Shanks is the source for entries through 1990, # and IATA SSIM is the source for entries after 1990. # # Another source occasionally used is Edward W. Whitman, World Time Differences, # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which # I found in the UCLA library. # # See the `europe' file for Greenland. # Canada # From Alain LaBont<e'> <ALB@immedia.ca> (1994-11-14): # I post here the time zone abbreviations standardized in Canada # for both English and French in the CAN/CSA-Z234.4-89 standard.... # # UTC Standard time Daylight savings time # offset French English French English # -2:30 - - HAT NDT # -3 - - HAA ADT # -3:30 HNT NST - - # -4 HNA AST HAE EDT # -5 HNE EST HAC CDT # -6 HNC CST HAR MDT # -7 HNR MST HAP PDT # -8 HNP PST HAY YDT # -9 HNY YST - - # # HN: Heure Normale ST: Standard Time # HA: Heure Avanc<e'>e DT: Daylight saving Time # # A: de l'Atlantique Atlantic # C: du Centre Central # E: de l'Est Eastern # M: Mountain # N: Newfoundland # P: du Pacifique Pacific # R: des Rocheuses # T: de Terre-Neuve # Y: du Yukon Yukon # # From Paul Eggert <eggert@twinsun.com> (1994-11-22): # Alas, this sort of thing must be handled by localization software. # The data for Canada are all from Shanks. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Canada 1918 only - Apr 14 2:00 1:00 D Rule Canada 1918 only - Oct 31 2:00 0 S Rule Canada 1942 only - Feb 9 2:00 1:00 D Rule Canada 1945 only - Sep 30 2:00 0 S Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D Rule Canada 1974 max - Oct lastSun 2:00 0 S Rule Canada 1987 max - Apr Sun>=1 2:00 1:00 D # Newfoundland (except Labrador) # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D Rule StJohns 1917 only - Sep 17 2:00 0 S Rule StJohns 1918 only - Oct 31 2:00 0 S # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks. Rule StJohns 1919 only - May 5 23:00 1:00 D Rule StJohns 1919 only - Aug 12 23:00 0 S # For 1931-1935 Whitman gives Apr same date; go with Shanks. Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S # For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman. Rule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D Rule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S # Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman. Rule StJohns 1942 only - Mar 1 0:00 1:00 D Rule StJohns 1942 only - Dec 31 0:00 0 S Rule StJohns 1943 only - May 30 0:00 1:00 D Rule StJohns 1943 only - Sep 5 0:00 0 S Rule StJohns 1944 only - Jul 10 0:00 1:00 D Rule StJohns 1944 only - Sep 2 0:00 0 S Rule StJohns 1945 only - Jan 1 0:00 1:00 D Rule StJohns 1945 only - Oct 7 2:00 0 S # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives # Apr 30 - Sep 24; go with Shanks. Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S Rule StJohns 1960 max - Oct lastSun 2:00 0 S Rule StJohns 1987 only - Apr Sun>=1 2:00 1:00 D Rule StJohns 1988 only - Apr Sun>=1 2:00 2:00 DD Rule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D # St John's has an apostrophe, but Posix file names can't have apostrophes. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/St_Johns -3:30:52 - LMT 1884 -3:30:52 StJohns N%sT 1935 Mar 30 -3:30 StJohns N%sT # east Labrador # The name `Happy Valley-Goose Bay' is too long; use `Goose Bay'. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay -3:30:52 StJohns NST 1919 -3:30:52 - NST 1935 Mar 30 -3:30 - NST 1936 -3:30 StJohns N%sT 1966 Mar 15 2:00 -4:00 StJohns A%sT # west Labrador, New Brunswick, Nova Scotia, Prince Edward I # From Paul Eggert (1996-06-12): # Shanks writes that since 1970 most of this region has been like Halifax. # Many locales did not observe peacetime DST until 1972; # Glace Bay, NS is the largest that we know of. # Shanks also writes that Liverpool, NS was the only town in Canada to observe # DST in 1971 but not 1970; for now we'll assume this is a typo. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Halifax 1916 only - Apr 1 0:00 1:00 D Rule Halifax 1916 only - Oct 1 0:00 0 S Rule Halifax 1918 only - Apr 14 2:00 1:00 D Rule Halifax 1918 only - Oct 31 2:00 0 S Rule Halifax 1920 only - May 9 0:00 1:00 D Rule Halifax 1920 only - Aug 29 0:00 0 S Rule Halifax 1921 only - May 6 0:00 1:00 D Rule Halifax 1921 1922 - Sep 5 0:00 0 S Rule Halifax 1922 only - Apr 30 0:00 1:00 D Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D Rule Halifax 1923 only - Sep 4 0:00 0 S Rule Halifax 1924 only - Sep 15 0:00 0 S Rule Halifax 1925 only - Sep 28 0:00 0 S Rule Halifax 1926 only - May 16 0:00 1:00 D Rule Halifax 1926 only - Sep 13 0:00 0 S Rule Halifax 1927 only - May 1 0:00 1:00 D Rule Halifax 1927 only - Sep 26 0:00 0 S Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D Rule Halifax 1928 only - Sep 9 0:00 0 S Rule Halifax 1929 only - Sep 3 0:00 0 S Rule Halifax 1930 only - Sep 15 0:00 0 S Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S Rule Halifax 1933 only - Apr 30 0:00 1:00 D Rule Halifax 1933 only - Oct 2 0:00 0 S Rule Halifax 1934 only - May 20 0:00 1:00 D Rule Halifax 1934 only - Sep 16 0:00 0 S Rule Halifax 1935 only - Jun 2 0:00 1:00 D Rule Halifax 1935 only - Sep 30 0:00 0 S Rule Halifax 1936 only - Jun 1 0:00 1:00 D Rule Halifax 1936 only - Sep 14 0:00 0 S Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S Rule Halifax 1939 only - May 28 0:00 1:00 D Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D Rule Halifax 1942 only - Feb 9 2:00 1:00 D Rule Halifax 1945 1959 - Sep lastSun 2:00 0 S Rule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D Rule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D Rule Halifax 1962 max - Oct lastSun 2:00 0 S Rule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Halifax -4:14:24 - LMT 1902 Jun 15 -4:00 Halifax A%sT Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15 -4:00 Canada A%sT 1953 -4:00 Halifax A%sT 1954 -4:00 - AST 1972 -4:00 Halifax A%sT # Ontario, Quebec # From Paul Eggert (1996-06-12): # Shanks writes that since 1970 most of this region has been like Montreal. # Thunder Bay skipped DST in 1973. # Many smaller locales did not observe peacetime DST until 1974; # Nipigon (EST) and Rainy River (CST) are the largest that we know of. # Far west Ontario is like Winnipeg; far east Quebec is like Halifax. # From Paul Eggert (1997-10-17): # msb@sq.com writes that an article in the 1997-10-14 Toronto Star # says that Atikokan, Ontario currently does not observe DST, # but will vote on 11-10 whether to use EST/EDT. # He also writes that the # <a href="http://www.gov.on.ca/MBS/english/publications/statregs/conttext.html"> # Ontario Time Act (1990, Chapter T.9) # </a> # says that Ontario east of 90W uses EST/EDT, and west of 90W uses CST/CDT. # Officially Atikokan is therefore on CST/CDT, and most likely this report # concerns a non-official time observed as a matter of local practice. # For what it's worth, Shanks says that Atikokan has agreed with # Rainy River ever since standard time was introduced. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Mont 1917 only - Mar 25 2:00 1:00 D Rule Mont 1917 only - Apr 24 0:00 0 S Rule Mont 1918 only - Apr 14 2:00 1:00 D Rule Mont 1918 only - Oct 31 2:00 0 S Rule Mont 1919 only - Mar 31 2:30 1:00 D Rule Mont 1919 only - Oct 25 2:30 0 S Rule Mont 1920 only - May 2 2:30 1:00 D Rule Mont 1920 only - Oct 3 2:30 0 S Rule Mont 1921 only - May 1 2:00 1:00 D Rule Mont 1921 only - Oct 2 2:30 0 S Rule Mont 1922 only - Apr 30 2:00 1:00 D Rule Mont 1922 only - Oct 1 2:30 0 S Rule Mont 1924 only - May 17 2:00 1:00 D Rule Mont 1924 1926 - Sep lastSun 2:30 0 S Rule Mont 1925 1926 - May Sun>=1 2:00 1:00 D Rule Mont 1927 only - May 1 0:00 1:00 D Rule Mont 1927 1932 - Sep Sun>=25 0:00 0 S Rule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D Rule Mont 1932 only - May 1 0:00 1:00 D Rule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D Rule Mont 1933 only - Oct 1 0:00 0 S Rule Mont 1934 1939 - Sep Sun>=24 0:00 0 S Rule Mont 1945 1948 - Sep lastSun 2:00 0 S Rule Mont 1946 1986 - Apr lastSun 2:00 1:00 D Rule Mont 1949 1950 - Oct lastSun 2:00 0 S Rule Mont 1951 1956 - Sep lastSun 2:00 0 S Rule Mont 1957 max - Oct lastSun 2:00 0 S Rule Mont 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Montreal -4:54:16 - LMT 1884 -5:00 Mont E%sT Zone America/Thunder_Bay -5:57:00 - LMT 1895 -5:00 Canada E%sT 1970 -5:00 Mont E%sT 1973 -5:00 - EST 1974 -5:00 Canada E%sT Zone America/Nipigon -5:53:04 - LMT 1895 -5:00 Canada E%sT Zone America/Rainy_River -6:17:56 - LMT 1895 -6:00 Canada C%sT # Manitoba # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Winn 1916 only - Apr 23 0:00 1:00 D Rule Winn 1916 only - Sep 17 0:00 0 S Rule Winn 1918 only - Apr 14 2:00 1:00 D Rule Winn 1918 only - Oct 31 2:00 0 S Rule Winn 1937 only - May 16 2:00 1:00 D Rule Winn 1937 only - Sep 26 2:00 0 S Rule Winn 1942 only - Feb 9 2:00 1:00 D Rule Winn 1945 only - Sep lastSun 2:00 0 S Rule Winn 1946 only - May 12 2:00 1:00 D Rule Winn 1946 only - Oct 13 2:00 0 S Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D Rule Winn 1947 1949 - Sep lastSun 2:00 0 S Rule Winn 1950 only - May 1 2:00 1:00 D Rule Winn 1950 only - Sep 30 2:00 0 S Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D Rule Winn 1951 1958 - Sep lastSun 2:00 0 S Rule Winn 1959 only - Oct lastSun 2:00 0 S Rule Winn 1960 only - Sep lastSun 2:00 0 S Rule Winn 1963 only - Apr lastSun 2:00 1:00 D Rule Winn 1963 only - Sep 22 2:00 0 S Rule Winn 1966 1986 - Apr lastSun 2:00 1:00 D Rule Winn 1966 max - Oct lastSun 2:00 0 S Rule Winn 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16 -6:00 Winn C%sT # Saskatchewan # From Paul Eggert (1996-06-12): # Shanks writes that since 1970 most of this region has been like Regina. # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972. # Other western towns (e.g. Lloydminster) are like Edmonton. # From W. Jones <jones@skdad.usask.ca> (1992-11-06): # The. . .below is based on information I got from our law library, the # provincial archives, and the provincial Community Services department. # A precise history would require digging through newspaper archives, and # since you didn't say what you wanted, I didn't bother. # # Saskatchewan is split by a time zone meridian (105W) and over the years # the boundary became pretty ragged as communities near it reevaluated # their affiliations in one direction or the other. In 1965 a provincial # referendum favoured legislating common time practices. # # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of # Saskatchewan 1978) was proclaimed, and established that the eastern # part of Saskatchewan would use CST year round, that districts in # northwest Saskatchewan would by default follow CST but could opt to # follow Mountain Time rules (thus 1 hour difference in the winter and # zero in the summer), and that districts in southwest Saskatchewan would # by default follow MT but could opt to follow CST. # # It took a few years for the dust to settle (I know one story of a town # on one time zone having its school in another, such that a mom had to # serve her family lunch in two shifts), but presently it seems that only # a few towns on the border with Alberta (e.g. Lloydminster) follow MT # rules any more; all other districts appear to have used CST year round # since sometime in the 1960s. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Regina 1918 only - Apr 14 2:00 1:00 D Rule Regina 1918 only - Oct 31 2:00 0 S Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D Rule Regina 1937 only - Oct Sun>=8 0:00 0 S Rule Regina 1938 only - Oct Sun>=1 0:00 0 S Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S Rule Regina 1942 only - Feb 9 2:00 1:00 D Rule Regina 1945 only - Sep lastSun 2:00 0 S Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D Rule Regina 1946 only - Oct Sun>=8 2:00 0 S Rule Regina 1947 1959 - Apr lastSun 2:00 1:00 D Rule Regina 1947 1958 - Sep lastSun 2:00 0 S Rule Regina 1959 only - Oct lastSun 2:00 0 S # Rule Swift 1957 only - Apr lastSun 2:00 1:00 D Rule Swift 1957 only - Oct lastSun 2:00 0 S Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D Rule Swift 1959 only - Oct lastSun 2:00 0 S Rule Swift 1960 1961 - Sep lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Regina -6:58:36 - LMT 1905 Sep -7:00 Regina M%sT 1960 Apr lastSun 2:00 -6:00 - CST Zone America/Swift_Current -7:11:20 - LMT 1905 Sep -7:00 Canada M%sT 1946 Apr lastSun 2:00 -7:00 Regina M%sT 1950 -7:00 Swift M%sT 1972 Apr lastSun 2:00 -6:00 - CST # Alberta # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D Rule Edm 1918 only - Oct 31 2:00 0 S Rule Edm 1919 only - May 27 2:00 0 S Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D Rule Edm 1920 only - Oct lastSun 2:00 0 S Rule Edm 1921 1923 - Sep lastSun 2:00 0 S Rule Edm 1942 only - Feb 9 2:00 1:00 D Rule Edm 1945 only - Sep lastSun 2:00 0 S Rule Edm 1947 only - Apr lastSun 2:00 1:00 D Rule Edm 1947 only - Sep lastSun 2:00 0 S Rule Edm 1967 only - Apr lastSun 2:00 1:00 D Rule Edm 1967 only - Oct lastSun 2:00 0 S Rule Edm 1969 only - Apr lastSun 2:00 1:00 D Rule Edm 1969 only - Oct lastSun 2:00 0 S Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D Rule Edm 1972 max - Oct lastSun 2:00 0 S Rule Edm 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Edmonton -7:33:52 - LMT 1906 Sep -7:00 Edm M%sT # British Columbia # From Paul Eggert (1996-06-12): # Shanks writes that since 1970 most of this region has been like Vancouver. # Dawson Creek uses MST. Much of east BC is like Edmonton. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Vanc 1918 only - Apr 14 2:00 1:00 D Rule Vanc 1918 only - Oct 31 2:00 0 S Rule Vanc 1942 only - Feb 9 2:00 1:00 D Rule Vanc 1945 only - Sep 30 2:00 0 S Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D Rule Vanc 1946 only - Oct 13 2:00 0 S Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S Rule Vanc 1962 max - Oct lastSun 2:00 0 S Rule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Vancouver -8:12:28 - LMT 1884 -8:00 Vanc P%sT Zone America/Dawson_Creek -8:00:56 - LMT 1884 -8:00 Canada P%sT 1947 -8:00 Vanc P%sT 1972 Aug 30 2:00 -7:00 - MST # Northwest Territories, Nunavut, Yukon # From Paul Eggert (1999-10-29): # Dawson switched to PST in 1973. Inuvik switched to MST in 1979. # Mathew Englander <mathew@io.org> (1996-10-07) gives the following refs: # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68, # c. 7 defines Yukon standard time as UTC-9. This is still valid; # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1). # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00. # * O.I.C. 1980/02 established DST. # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00. # Shanks says Yukon's 1973-10-28 switch was at 2:00; go with Englander. # From Rives McDow (1999-09-04): # Nunavut ... moved ... to incorporate the whole territory into one time zone. # <a href="http://www.nunatsiaq.com/nunavut/nvt90903_13.html"> # Nunavut moves to single time zone Oct. 31 # </a> # # From Antoine Leca (1999-09-06): # We then need to create a new timezone for the Kitikmeot region of Nunavut # to differentiate it from the Yellowknife region. # From Paul Eggert (1999-09-20): # <a href="http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html"> # Basic Facts: The New Territory # </a> (1999) reports that Pangnirtung operates on Eastern time, # and that Coral Harbour does not observe DST. We don't know when # Pangnirtung switched to Eastern time; we'll guess 1995. # We'll ignore the claim about Coral Harbour for now, # since we have no further info. # From Rives McDow (1999-11-08): # On October 31, when the rest of Nunavut went to Central time, # Pangnirtung wobbled. Here is the result of their wobble: # # The following businesses and organizations in Pangnirtung use Central Time: # # First Air, Power Corp, Nunavut Construction, Health Center, RCMP, # Eastern Arctic National Parks, A & D Specialist # # The following businesses and organizations in Pangnirtung use Eastern Time: # # Hamlet office, All other businesses, Both schools, Airport operator # # This has made for an interesting situation there, which warranted the news. # No one there that I spoke with seems concerned, or has plans to # change the local methods of keeping time, as it evidently does not # really interfere with any activities or make things difficult locally. # They plan to celebrate New Year's turn-over twice, one hour apart, # so it appears that the situation will last at least that long. # The Nunavut Intergovernmental Affairs hopes that they will "come to # their senses", but the locals evidently don't see any problem with # the current state of affairs. # From Michaela Rodrigue, writing in the # <a href="http://www.nunatsiaq.com/archives/nunavut991130/nvt91119_17.html"> # Nunatsiaq News (1999-11-19)</a>: # Clyde River, Pangnirtung and Sanikiluaq now operate with two time zones, # central - or Nunavut time - for government offices, and eastern time # for municipal offices and schools.... Igloolik [was similar but then] # made the switch to central time on Saturday, Nov. 6. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule NT_YK 1918 only - Apr 14 2:00 1:00 D Rule NT_YK 1918 only - Oct 27 2:00 0 S Rule NT_YK 1919 only - May 25 2:00 1:00 D Rule NT_YK 1919 only - Nov 1 0:00 0 S Rule NT_YK 1942 only - Feb 9 2:00 1:00 D Rule NT_YK 1945 only - Sep 30 2:00 0 S Rule NT_YK 1965 only - Apr lastSun 0:00 2:00 DD Rule NT_YK 1965 only - Oct lastSun 2:00 0 S Rule NT_YK 1980 1986 - Apr lastSun 2:00 1:00 D Rule NT_YK 1980 max - Oct lastSun 2:00 0 S Rule NT_YK 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Pangnirtung -4:22:56 - LMT 1884 -4:00 NT_YK A%sT 1995 Apr Sun>=1 2:00 -5:00 Canada E%sT 1999 Oct 31 2:00 -6:00 Canada C%sT Zone America/Iqaluit -4:33:52 - LMT 1884 # Frobisher Bay before 1987 -5:00 NT_YK E%sT 1999 Oct 31 2:00 -6:00 Canada C%sT Zone America/Rankin_Inlet -6:08:40 - LMT 1884 -6:00 NT_YK C%sT Zone America/Cambridge_Bay -7:00:20 - LMT 1884 -7:00 NT_YK M%sT 1999 Oct 31 2:00 -6:00 Canada C%sT Zone America/Yellowknife -7:37:24 - LMT 1884 -7:00 NT_YK M%sT Zone America/Inuvik -8:54:00 - LMT 1884 -8:00 NT_YK P%sT 1979 Apr lastSun 2:00 -7:00 NT_YK M%sT Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20 -9:00 NT_YK Y%sT 1966 Jul 1 2:00 -8:00 NT_YK P%sT Zone America/Dawson -9:17:40 - LMT 1900 Aug 20 -9:00 NT_YK Y%sT 1973 Oct 28 0:00 -8:00 NT_YK P%sT ############################################################################### # Mexico # From Guy Harris: # Rules are from the Official Airline Guide, Worldwide Edition, for 1987. # Rules [before] 1987 are unknown. # The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana # observe DST." This is presumably Baja California Norte, above 28th parallel, # as listed there; [there is also] "Baja California Sur and N. Pacific # Coast (States of Sinaloa and Sonora)." # From Bob Devine (1988-01-28): # The Federal District (where Mexico City is) has observed [DST] several # times but not recently. # # I don't where to draw the line in the North Baja area. 28th latitude # sounds good -- but it may be higher (how far [d]o radio stations from # San Diego affect culture?). # # The dates of DST probably go back to 1981. The rules are the same as # US's. This is going to be a headache for US presidential electi[o]n years! # From Arthur David Olson (1988-02-13) # Since the 1981 starting date is only "probable," we'll keep the 1987 # starting date below. # From U. S. Naval Observatory (1989-01-19): # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND # MEXICO BAJA CAL N N. PACIFIC COAST (STATES # MEXICO BAJA CAL N OF SINALOA AND SONORA) # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLEL APR 3 # MEXICO BAJA CAL N - OCT 29 # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLEL APR 3 # MEXICO BAJA CAL N - 0CT 29 # MEXICO 6 H BEHIND UTC STATES OF DURANGO, # MEXICO COAHUILA, NUEVO LEON, # MEXICO TAMAULIPAS # MEXICO 5 H BEHIND UTC STATES OF DURANGO, # MEXICO COAHUILA, NUEVO LEON, # MEXICO TAMAULIPAS APR 3 - OCT 29 # MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF # MEXICO CAMPECHE, QUINTANA ROO AND # MEXICO YUCATAN # From Arthur David Olson (1989-01-21): # April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem. # USNO claims there should be four Mexican zones rather than three: # a zone that's GMT-8 with DST; a zone that's always GMT-7; # a zone that's GMT-6 with DST; and a zone that's always GMT-6. # From Alan Perry <alan.perry@eng.sun.com> (1996-02-15): # A guy from our Mexico subsidiary finally found the Presidential Decree # outlining the timezone changes in Mexico. # # ------------- Begin Forwarded Message ------------- # # I finally got my hands on the Official Presidential Decree that sets up the # rules for the DST changes. The rules are: # # 1. The country is divided in 3 timezones: # - Baja California Norte (the Mexico/BajaNorte TZ) # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ) # - The rest of the country (the Mexico/General TZ) # # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October # at 2:00 AM, the times in each zone are as follows: # BajaNorte: GMT+7 # BajaSur: GMT+6 # General: GMT+5 # # 3. The rest of the year, the times are as follows: # BajaNorte: GMT+8 # BajaSur: GMT+7 # General: GMT+6 # # The Decree was published in Mexico's Official Newspaper on January 4th. # # -------------- End Forwarded Message -------------- # From Paul Eggert (1996-06-12): # For an English translation of the decree, see # <a href="http://mexico-travel.com/extra/timezone_eng.html"> # ``Diario Oficial: Time Zone Changeover'' (1996-01-04). # </a> # From Rives McDow (1998-10-08): # The State of Quintana Roo has reverted back to central STD and DST times # (i.e. UTC -0600 and -0500 as of 1998-08-02). # From Rives McDow (2000-01-10): # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time # zone 5 hours from the International Date Line, and will not observe daylight # savings time so as to stay on the same time zone as the southern part of # Arizona year round. # From Shanks: # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Mexico 1939 only - Feb 5 0:00 1:00 D Rule Mexico 1939 only - Jun 25 0:00 0 S Rule Mexico 1940 only - Dec 9 0:00 1:00 D Rule Mexico 1941 only - Apr 1 0:00 0 S Rule Mexico 1943 only - Dec 16 0:00 1:00 D Rule Mexico 1944 only - May 1 0:00 0 S Rule Mexico 1950 only - Feb 12 0:00 1:00 D Rule Mexico 1950 only - Jul 30 0:00 0 S Rule Mexico 1996 max - Apr Sun>=1 2:00 1:00 D Rule Mexico 1996 max - Oct lastSun 2:00 0 S # Rule BajaN 1954 1961 - Apr lastSun 2:00 1:00 D Rule BajaN 1954 1961 - Sep lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] # Quintana Roo Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 0:12:56 -6:00 - CST 1996 -6:00 Mexico C%sT 1997 Oct lastSun 2:00 -5:00 Mexico E%sT 1998 Aug 2 2:00 -6:00 Mexico C%sT # Central Mexico Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24 -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 - MST 1931 May 1 23:00 -6:00 - CST 1931 Oct -7:00 - MST 1932 Mar 30 23:00 -6:00 Mexico C%sT # Chihuahua Zone America/Chihuahua -7:04:20 - LMT 1921 Dec 31 23:55:40 -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 - MST 1931 May 1 23:00 -6:00 - CST 1931 Oct -7:00 - MST 1932 Mar 30 23:00 -6:00 - CST 1996 -6:00 Mexico C%sT 1998 -6:00 - CST 1998 Apr Sun>=1 3:00 -7:00 Mexico M%sT # Sonora Zone America/Hermosillo -7:23:52 - LMT 1921 Dec 31 23:36:08 -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 - MST 1931 May 1 23:00 -6:00 - CST 1931 Oct -7:00 - MST 1932 Mar 30 23:00 -6:00 - CST 1942 Apr -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT 1999 -7:00 - MST # S Baja California, Nayarit, Sinaloa Zone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20 -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 - MST 1931 May 1 23:00 -6:00 - CST 1931 Oct -7:00 - MST 1932 Mar 30 23:00 -6:00 - CST 1942 Apr -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT # Baja California Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56 -8:00 - PST 1927 Jun 10 23:00 -7:00 - MST 1930 Nov 16 -8:00 - PST 1942 Apr -7:00 - MST 1949 Jan 14 -8:00 BajaN P%sT 1976 -8:00 US P%sT 1996 -8:00 Mexico P%sT # # Revillagigedo Is # no information ############################################################################### # Anguilla # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Anguilla -4:12:16 - LMT 1912 Mar 2 -4:00 - AST # Antigua and Barbuda # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Antigua -4:07:12 - LMT 1912 Mar 2 -5:00 - EST 1951 -4:00 - AST # Bahamas # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Bahamas 1964 max - Oct lastSun 2:00 0 S Rule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D Rule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Nassau -5:09:24 - LMT 1912 Mar 2 -5:00 Bahamas E%sT # Barbados # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Barb 1977 only - Jun 12 2:00 1:00 D Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D Rule Barb 1979 only - Sep 30 2:00 0 S Rule Barb 1980 only - Sep 25 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Barbados -3:58:28 - LMT 1924 # Bridgetown -3:58:28 - BMT 1932 # Bridgetown Mean Time -4:00 Barb A%sT # Belize # Whitman entirely disagrees with Shanks; go with Shanks. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD Rule Belize 1919 1943 - Feb Sun>=9 0:00 0 S Rule Belize 1973 only - Dec 5 0:00 1:00 D Rule Belize 1974 only - Feb 9 0:00 0 S Rule Belize 1982 only - Dec 18 0:00 1:00 D Rule Belize 1983 only - Feb 12 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Belize -5:52:48 - LMT 1912 Apr -6:00 Belize C%sT # Bermuda # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton -4:00 - AST 1974 Apr 28 2:00 -4:00 Bahamas A%sT # Cayman Is # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Cayman -5:25:32 - LMT 1890 # Georgetown -5:07:12 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST # Costa Rica # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D # IATA SSIM (1991-09) says the following was at 1:00; go with Shanks. Rule CR 1991 only - Jul 1 0:00 0 S Rule CR 1992 only - Mar 15 0:00 0 S # There are too many San Joses elsewhere, so we'll use `Costa Rica'. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose -5:36:20 - SJMT 1921 Jan 15 # San Jose Mean Time -6:00 CR C%sT # Coco # no information; probably like America/Costa_Rica # Cuba # From Arthur David Olson (1999-03-29): # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between # the Cuban National Team and the Baltimore Orioles was carried live on # the Orioles Radio Network, including affiliate WTOP in Washington, DC. # During the game, play-by-play announcer Jim Hunter noted that # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving # Time today." (The "two hour" remark referred to losing one hour of # sleep on 1999-03-28--when the announcers were in Cuba as it switched # to DST--and one more hour on 1999-04-04--when the announcers will have # returned to Baltimore, which switches on that date.) # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Cuba 1928 only - Jun 10 0:00 1:00 D Rule Cuba 1928 only - Oct 10 0:00 0 S Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S Rule Cuba 1965 only - Jun 1 0:00 1:00 D Rule Cuba 1965 only - Sep 30 0:00 0 S Rule Cuba 1966 only - May 29 0:00 1:00 D Rule Cuba 1966 only - Oct 2 0:00 0 S Rule Cuba 1967 only - Apr 8 0:00 1:00 D Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S Rule Cuba 1968 only - Apr 14 0:00 1:00 D Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S Rule Cuba 1972 1974 - Oct 8 0:00 0 S Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S Rule Cuba 1978 only - May 7 0:00 1:00 D Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S Rule Cuba 1996 only - Oct 6 0:00s 0 S Rule Cuba 1997 only - Oct 12 0:00s 0 S Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D Rule Cuba 1998 max - Oct lastSun 0:00s 0 S Rule Cuba 2000 max - Apr Sun>=1 0:00s 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Havana -5:29:28 - LMT 1890 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT -5:00 Cuba C%sT # Dominica # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau -4:00 - AST # Dominican Republic # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule DR 1966 only - Oct 30 0:00 1:00 D Rule DR 1967 only - Feb 28 0:00 0 S Rule DR 1969 1973 - Oct lastSun 0:00 0:30 HD Rule DR 1970 only - Feb 21 0:00 0 S Rule DR 1971 only - Jan 20 0:00 0 S Rule DR 1972 1974 - Jan 21 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Santo_Domingo -4:39:36 - LMT 1890 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT -5:00 DR E%sT 1974 Oct 27 -4:00 - AST # El Salvador # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D Rule Salv 1987 1988 - Sep lastSun 0:00 0 S # There are too many San Salvadors elsewhere, so we'll use `El Salvador'. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador -6:00 Salv C%sT # Grenada # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Grenada -4:07:00 - LMT 1911 Jul # St George's -4:00 - AST # Guadeloupe # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre -4:00 - AST # Guatemala # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Guat 1973 only - Nov 25 0:00 1:00 D Rule Guat 1974 only - Feb 24 0:00 0 S Rule Guat 1983 only - May 21 0:00 1:00 D Rule Guat 1983 only - Sep 22 0:00 0 S Rule Guat 1991 only - Mar 23 0:00 1:00 D Rule Guat 1991 only - Sep 7 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5 -6:00 Guat C%sT # Haiti # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Haiti 1983 only - May 8 0:00 1:00 D Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S # Shanks says AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. Go with IATA. Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Port-au-Prince -4:49:20 - LMT 1890 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT -5:00 Haiti E%sT # Honduras # Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr -6:00 Salv C%sT # # Great Swan I ceded by US to Honduras in 1972 # Jamaica # From Bob Devine (1988-01-28): # Follows US rules. # From U. S. Naval Observatory (1989-01-19): # JAMAICA 5 H BEHIND UTC # From Shanks: # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Jamaica -5:07:12 - LMT 1890 # Kingston -5:07:12 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST 1974 Apr 28 2:00 -5:00 US E%sT 1984 -5:00 - EST # Martinique # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France -4:04 - FFMT 1911 May # Fort-de-France MT -4:00 - AST 1980 Apr 6 -4:00 1:00 ADT 1980 Sep 28 -4:00 - AST # Montserrat # From Paul Eggert (1997-08-31): # Recent volcanic eruptions have forced evacuation of Plymouth, the capital. # Luckily, Olveston, the current de facto capital, has the same longitude. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Olveston -4:00 - AST # Nicaragua # # From Steffen Thorsen (1998-12-29): # Nicaragua seems to be back at -6:00 but I have not been able to find when # they changed from -5:00. # # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S Rule Nic 1992 only - Jan 1 4:00 1:00 D Rule Nic 1992 only - Sep 24 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Managua -5:45:08 - LMT 1890 -5:45 - MMT 1934 Jun 23 # Managua Mean Time -6:00 - CST 1973 May -5:00 - EST 1975 Feb 16 -6:00 Nic C%sT 1993 Jan 1 4:00 -5:00 - EST 1998 Dec -6:00 - CST # Panama # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Panama -5:18:08 - LMT 1890 -5:20 - PMT 1908 Apr 22 # Panama Mean Time -5:00 - EST # Puerto Rico # There are too many San Juans elsewhere, so we'll use `Puerto_Rico'. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan -4:00 - AST 1942 May 3 -4:00 1:00 AWT 1945 Sep 30 2:00 -4:00 - AST # St Kitts-Nevis # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre -4:00 - AST # St Lucia # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/St_Lucia -4:04:00 - LMT 1890 # Castries -4:04 - CMT 1912 # Castries Mean Time -4:00 - AST # St Pierre and Miquelon # There are too many St Pierres elsewhere, so we'll use `Miquelon'. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre -4:00 - AST 1980 May -3:00 Mont PM%sT # Pierre & Miquelon Time # St Vincent and the Grenadines # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown -4:04:56 - KMT 1912 # Kingstown Mean Time -4:00 - AST # Turks and Caicos # From Paul Eggert (1998-08-06): # Shanks says they use US DST rules, but IATA SSIM (1991/1998) # says they switch at midnight. Go with IATA SSIM. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule TC 1979 1986 - Apr lastSun 0:00 1:00 D Rule TC 1979 max - Oct lastSun 0:00 0 S Rule TC 1987 max - Apr Sun>=1 0:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Grand_Turk -4:44:32 - LMT 1890 -5:07:12 - KMT 1912 Feb # Kingston Mean Time -5:00 TC E%sT # British Virgin Is # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town -4:00 - AST # Virgin Is # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/St_Thomas -4:19:44 - LMT 1911 Jul # Charlotte Amalie -4:00 - AST