northamerica revision 2742
12742Swollman# @(#)northamerica 7.11 22742Swollman# also includes Central America and the Caribbean 32742Swollman 42742Swollman# This data is by no means authoritative; if you think you know better, 52742Swollman# go ahead and edit the file (and please send any changes to 62742Swollman# tz@elsie.nci.nih.gov for general use in the future). 72742Swollman 82742Swollman# From Paul Eggert <eggert@twinsun.com> (August 17, 1994): 92742Swollman# A reliable and entertaining source about time zones is 102742Swollman# Derek Howse, Greenwich time and the discovery of the longitude, 112742Swollman# Oxford University Press (1980). 122742Swollman 132742Swollman############################################################################### 142742Swollman 152742Swollman# United States 162742Swollman 172742Swollman# From Arthur David Olson: 182742Swollman# US Daylight Saving Time ended on the last Sunday of *October* in 1974. 192742Swollman# See, for example, the front page of the Saturday, October 26, 1974 202742Swollman# and Sunday, October 27, 1974 editions of the Washington Post. 212742Swollman 222742Swollman# From seismo!munnari!kre: 232742Swollman# I recall also being told by someone once that Canada didn't have 242742Swollman# the DST variations in 74/75 that the US did, but I am not nearly 252742Swollman# sure enough of this to add anything. 262742Swollman 272742Swollman# From Arthur David Olson: 282742Swollman# The above has been confirmed by Bob Devine; we'll go with it here. 292742Swollman 302742Swollman# From Arthur David Olson: 312742Swollman# Before the Uniform Time Act of 1966 took effect in 1967, observance of 322742Swollman# Daylight Saving Time in the US was by local option, except during wartime. 332742Swollman 342742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 352742SwollmanRule US 1918 1919 - Mar lastSun 2:00 1:00 D 362742SwollmanRule US 1918 1919 - Oct lastSun 2:00 0 S 372742SwollmanRule US 1942 only - Feb 9 2:00 1:00 W # War 382742SwollmanRule US 1945 only - Sep 30 2:00 0 S 392742SwollmanRule US 1967 max - Oct lastSun 2:00 0 S 402742SwollmanRule US 1967 1973 - Apr lastSun 2:00 1:00 D 412742SwollmanRule US 1974 only - Jan 6 2:00 1:00 D 422742SwollmanRule US 1975 only - Feb 23 2:00 1:00 D 432742SwollmanRule US 1976 1986 - Apr lastSun 2:00 1:00 D 442742SwollmanRule US 1987 max - Apr Sun>=1 2:00 1:00 D 452742Swollman 462742Swollman# From Bob Devine (January 28, 1988): 472742Swollman# ...Alaska (and Hawaii) had the timezone names changed in 1967. 482742Swollman# old new 492742Swollman# Pacific Standard Time(PST) -same- 502742Swollman# Yukon Standard Time(YST) -same- 512742Swollman# Central Alaska S.T. (CAT) Alaska-Hawaii St[an]dard Time (AHST) 522742Swollman# Nome Standard Time (NT) Bering Standard Time (BST) 532742Swollman# 542742Swollman# ...Alaska's timezone lines were redrawn in 1983 to give only 2 tz. 552742Swollman# The YST zone now covers nearly all of the state, AHST just part 562742Swollman# of the Aleutian islands. No DST. 572742Swollman 582742Swollman# From U. S. Naval Observatory (January 19, 1989): 592742Swollman# USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON 602742Swollman# USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30 612742Swollman# USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON 622742Swollman# USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30 632742Swollman# USA MOUNTAIN 7 H BEHIND UTC DENVER 642742Swollman# USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30 652742Swollman# USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO 662742Swollman# USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30 672742Swollman# USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST) 682742Swollman# USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT) 692742Swollman# USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W 702742Swollman# USA - " - 9 H BEHIND UTC APR 3 - OCT 30 712742Swollman# USA HAWAII 10 H BEHIND UTC 722742Swollman# USA BERING 11 H BEHIND UTC SAMOA, MIDWAY 732742Swollman 742742Swollman# From Arthur David Olson (January 21, 1989): 752742Swollman# The above dates are for 1988. 762742Swollman# Note the "AKST" and "AKDT" abbreviations, the claim that there's 772742Swollman# no DST in Samoa, and the claim that there is DST in Alaska and the 782742Swollman# Aleutians. 792742Swollman 802742Swollman# From Arthur David Olson (February 13, 1988): 812742Swollman# Legal standard time zone names, from United States Code (1982 Edition and 822742Swollman# Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names 832742Swollman# up to April 1, 1967 (when most provisions of the Uniform Time Act of 1966 842742Swollman# took effect), as explained in sections 263 and 261: 852742Swollman# (none) 862742Swollman# United States standard eastern time 872742Swollman# United States standard mountain time 882742Swollman# United States standard central time 892742Swollman# United States standard Pacific time 902742Swollman# (none) 912742Swollman# United States standard Alaska time 922742Swollman# (none) 932742Swollman# Next, names from April 1, 1967 until November 30, 1983 (the date for 942742Swollman# public law 98-181): 952742Swollman# Atlantic standard time 962742Swollman# eastern standard time 972742Swollman# central standard time 982742Swollman# mountain standard time 992742Swollman# Pacific standard time 1002742Swollman# Yukon standard time 1012742Swollman# Alaska-Hawaii standard time 1022742Swollman# Bering standard time 1032742Swollman# And after November 30, 1983: 1042742Swollman# Atlantic standard time 1052742Swollman# eastern standard time 1062742Swollman# central standard time 1072742Swollman# mountain standard time 1082742Swollman# Pacific standard time 1092742Swollman# Alaska standard time 1102742Swollman# Hawaii-Aleutian standard time 1112742Swollman# Samoa standard time 1122742Swollman# The law doesn't give abbreviations. 1132742Swollman 1142742Swollman# From Paul Eggert <eggert@twinsun.com> (August 16, 1994): 1152742Swollman# Howse writes that Alaska switched from the Julian to the Gregorian calendar, 1162742Swollman# and from east-of-GMT to west-of-GMT days, in 1867 when the US purchased it 1172742Swollman# from Russia. We don't have this data pinned down yet, though. 1182742Swollman 1192742Swollman# Easy stuff first--including Alaska, where we ignore history (since we 1202742Swollman# can't tell if we should give Yukon time or Alaska-Hawaii time for "old" 1212742Swollman# times). 1222742Swollman 1232742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 1242742SwollmanZone America/New_York -5:00 US E%sT 1252742SwollmanZone America/Chicago -6:00 US C%sT 1262742SwollmanZone America/Denver -7:00 US M%sT 1272742SwollmanZone America/Los_Angeles -8:00 US P%sT 1282742SwollmanZone America/Anchorage -9:00 US AK%sT 1292742Swollman # AK%sT is the abbreviation per USNO 1302742Swollman 1312742Swollman# Mainland US areas that are always Standard as of 1986. 1322742Swollman 1332742SwollmanZone America/Fort_Wayne -5:00 US E%sT 1946 1342742Swollman -5:00 - EST # Always EST as of 1986 1352742Swollman# From Arthur David Olson (October 28, 1991): 1362742Swollman# An article on page A3 of the Sunday, October 27, 1991 Washington Post 1372742Swollman# notes that Starke County switched from Central time to Eastern time as of 1382742Swollman# October 27, 1991. 1392742SwollmanZone America/Knox_IN -6:00 US C%sT 1991 Oct 27 2:00 1402742Swollman -5:00 - EST # Always EST as of 1991 1412742SwollmanZone America/Phoenix -7:00 US M%sT 1946 1422742Swollman -7:00 - MST # Always MST as of 1986 1432742Swollman 1442742Swollman# From Arthur David Olson (February 13, 1988): 1452742Swollman# However. . .a writer from the Inter Tribal Council of Arizona, Inc., 1462742Swollman# notes in private correspondence dated 12/28/87 that "Presently, only the 1472742Swollman# Navajo Nation participates in the Daylight Saving Time policy, due to its 1482742Swollman# large size and location in three states." (The "only" means that other 1492742Swollman# tribal nations don't use DST.) 1502742Swollman 1512742SwollmanLink America/Denver Navajo 1522742Swollman 1532742Swollman# From Bob Devine (January 28, 1988): 1542742Swollman# Michigan didn't observe DST from 1968 to 1973. 1552742Swollman 1562742SwollmanZone America/Detroit -5:00 US E%sT 1968 1572742Swollman -5:00 - EST 1973 1582742Swollman -5:00 US E%sT 1592742Swollman 1602742Swollman# Samoa just changes names. No DST, per Naval Observatory. 1612742Swollman# 1622742Swollman# Howse writes that in 1879 the King of Samoa decided to change 1632742Swollman# ``the date in his kingdom from the Antipodean to the American system, 1642742Swollman# ordaining -- by a masterpiece of diplomatic flattery -- that 1652742Swollman# the Fourth of July should be celebrated twice in that year.'' 1662742Swollman 1672742SwollmanZone Pacific/Samoa 12:37:12 - LMT 1879 Jul 5 1682742Swollman -11:22:48 - LMT 1911 1692742Swollman -11:30 - SST 1950 1702742Swollman -11:00 - NST 1967 Apr # N=Nome 1712742Swollman -11:00 - BST 1983 Nov 30 # B=Bering 1722742Swollman -11:00 - SST # S=Samoa 1732742Swollman 1742742SwollmanZone Pacific/Midway -11:49:28 - LMT 1901 1752742Swollman -11:00 - NST 1967 Apr # N=Nome 1762742Swollman -11:00 - BST 1983 Nov 30 # B=Bering 1772742Swollman -11:00 - SST # S=Samoa 1782742Swollman 1792742Swollman# Aleutian has a name change. DST, per Naval Observatory. 1802742Swollman 1812742SwollmanZone America/Atka -10:00 US AH%sT 1983 Nov 30 1822742Swollman -10:00 US HA%sT 1832742Swollman 1842742Swollman# From Arthur David Olson: 1852742Swollman# And then there's Hawaii. 1862742Swollman# DST was observed for one day in 1933; 1872742Swollman# Standard time was change by half an hour in 1947; 1882742Swollman# it's always standard as of 1986. 1892742Swollman 1902742SwollmanZone Pacific/Honolulu -10:30 US H%sT 1933 Apr 30 2:00 1912742Swollman -10:30 1:00 HDT 1933 May 1 2:00 1922742Swollman -10:30 US H%sT 1947 Jun 8 2:00 1932742Swollman -10:00 - HST 1942742Swollman 1952742Swollman# Navassa 1962742Swollman# no information; probably like US/Eastern 1972742Swollman 1982742Swollman 1992742Swollman# Old names, for S5 users 2002742Swollman 2012742Swollman# Link LINK-FROM LINK-TO 2022742SwollmanLink America/New_York EST5EDT 2032742SwollmanLink America/Chicago CST6CDT 2042742SwollmanLink America/Denver MST7MDT 2052742SwollmanLink America/Los_Angeles PST8PDT 2062742SwollmanLink America/Fort_Wayne EST 2072742SwollmanLink America/Phoenix MST 2082742SwollmanLink Pacific/Honolulu HST 2092742Swollman 2102742Swollman################################################################################ 2112742Swollman 2122742Swollman 2132742Swollman# From Paul Eggert <eggert@twinsun.com> (November 18, 1993): 2142742Swollman# A good source for time zone historical data outside the U.S. is 2152742Swollman# Thomas G. Shanks, The International Atlas (3rd edition), 2162742Swollman# San Diego: ACS Publications, Inc. (1991). 2172742Swollman# Except where otherwise noted, it is the source for the data below. 2182742Swollman# 2192742Swollman# Another source occasionally used is Edward W. Whitman, World Time Differences, 2202742Swollman# Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), which 2212742Swollman# I found in the UCLA library. 2222742Swollman# 2232742Swollman# I invented the abbreviation SPST for St Pierre Standard Time; SPDT likewise. 2242742Swollman# Corrections are welcome! 2252742Swollman# 2262742Swollman# See the `africa' file for Zone naming conventions. 2272742Swollman 2282742Swollman 2292742Swollman 2302742Swollman# Canada 2312742Swollman 2322742Swollman# Canada is reportedly lots easier than the US--leastways since 1951. 2332742Swollman# I don't know what they did before then. 2342742Swollman# 4.3BSD claims that it's perfectly regular. 2352742Swollman# According to a posting in "comp.bugs.misc", "comp.unix.wizards", etc. 2362742Swollman# on February 8, 1987, by Dave Sherman of the Law Society of Upper Canada, 2372742Swollman# "...Canada (well, Ontario and at least some of the other provinces) are 2382742Swollman# adopting the new daylight savings time rules...". We assume all of 2392742Swollman# Canada is doing so. 2402742Swollman 2412742Swollman# From Bob Devine (January 28, 1988): 2422742Swollman# All of Canada did have DST from your first rule except Saskatchewan. 2432742Swollman# Which parts did not observe DST is hard to pinpoint but most of the 2442742Swollman# province follows the rules. 2452742Swollman# NOTE: those that didn't have DST for that rule, also 2462742Swollman# probably did not have it for several years previous. 2472742Swollman 2482742Swollman# From U. S. Naval Observatory (January 19, 1989): 2492742Swollman# CANADA NEW FDL 3.5H BEHIND UTC ST.JOHN'S 2502742Swollman# CANADA NEW FDL 1.5H BEHIND UTC APR 3 - OCT 29 2512742Swollman# CANADA ATLANTIC 4 H BEHIND UTC HALIFAX 2522742Swollman# CANADA ATLANTIC 3 H BEHIND UTC APR 3 - OCT 29 2532742Swollman# CANADA EASTERN 5 H BEHIND UTC TORONTO, MONTREAL, OTTAWA 2542742Swollman# CANADA EASTERN 4 H BEHIND UTC APR 3 - OCT 29 2552742Swollman# CANADA CENTRAL 6 H BEHIND UTC REGINA, WINNIPEG 2562742Swollman# CANADA CENTRAL 5 H BEHIND UTC APR 3 - OCT 29 2572742Swollman# CANADA MOUNTAIN 7 H BEHIND UTC CALGARY, EDMONTON 2582742Swollman# CANADA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 29 2592742Swollman# CANADA PACIFIC 8 H BEHIND UTC VANCOUVER 2602742Swollman# CANADA PACIFIC 7 H BEHIND UTC APR 3 - OCT 29 2612742Swollman# CANADA YUKON SAME AS PACIFIC DAWSON 2622742Swollman 2632742Swollman# From Arthur David Olson (January 21, 1989): 2642742Swollman# April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem. 2652742Swollman# Note claim that there's double DST in Newfoundland and that Yukon should 2662742Swollman# be same as Pacific. 2672742Swollman 2682742Swollman# From W. Jones (jones@skdad.usask.ca) (November 6, 1992): 2692742Swollman# The. . .below is based on information I got from our law library, the 2702742Swollman# provincial archives, and the provincial Community Services department. 2712742Swollman# A precise history would require digging through newspaper archives, and 2722742Swollman# since you didn't say what you wanted, I didn't bother. 2732742Swollman# 2742742Swollman# Saskatchewan is split by a time zone meridian (105W) and over the years 2752742Swollman# the boundary became pretty ragged as communities near it reevaluated 2762742Swollman# their affiliations in one direction or the other. In 1965 a provincial 2772742Swollman# referendum favoured legislating common time practices. 2782742Swollman# 2792742Swollman# On 15 April 1966 the Time Act (c. T-14, Revised Statutes of 2802742Swollman# Saskatchewan 1978) was proclaimed, and established that the eastern 2812742Swollman# part of Saskatchewan would use CST year round, that districts in 2822742Swollman# northwest Saskatchewan would by default follow CST but could opt to 2832742Swollman# follow Mountain Time rules (thus 1 hour difference in the winter and 2842742Swollman# zero in the summer), and that districts in southwest Saskatchewan would 2852742Swollman# by default follow MT but could opt to follow CST. 2862742Swollman# 2872742Swollman# It took a few years for the dust to settle (I know one story of a town 2882742Swollman# on one time zone having its school in another, such that a mom had to 2892742Swollman# serve her family lunch in two shifts), but presently it seems that only 2902742Swollman# a few towns on the border with Alberta (e.g. Lloydminster) follow MT 2912742Swollman# rules any more; all other districts appear to have used CST year round 2922742Swollman# since sometime in the 1960s. 2932742Swollman# 2942742Swollman# Here's how I would summarize things. Establish a "Saskatchewan" CST 2952742Swollman# time zone, and note that it officially exists as of 15 April 1966. Any 2962742Swollman# current exceptions can put themselves in the "Mountain" zone, since 2972742Swollman# those are the rules they follow. Any past exceptions can be forgotten, 2982742Swollman# since that's what those who live here have done. 2992742Swollman 3002742Swollman# From Arthur David Olson (November 21, 1992): 3012742Swollman# East-Saskatchewan kept to avoid problems for folks using that zone by name; 3022742Swollman# plain Saskatchewan added. 3032742Swollman 3042742Swollman 3052742Swollman# From Shanks (1991): 3062742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 3072742SwollmanRule StJohns 1884 only - Jan 1 0:00 0 S 3082742SwollmanRule StJohns 1917 1918 - Apr Sun>=8 2:00 1:00 D 3092742SwollmanRule StJohns 1917 only - Sep 17 2:00 0 S 3102742SwollmanRule StJohns 1918 only - Oct 31 2:00 0 S 3112742Swollman# Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks. 3122742SwollmanRule StJohns 1919 only - May 5 23:00 1:00 D 3132742SwollmanRule StJohns 1919 only - Aug 12 23:00 0 S 3142742Swollman# For 1931-1935 Whitman gives Apr same date; go with Shanks. 3152742SwollmanRule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D 3162742SwollmanRule StJohns 1920 1935 - Oct lastSun 23:00 0 S 3172742Swollman# For 1936-1941 Shanks gives May Mon>=9 and Oct Mon>=2; go with Whitman. 3182742SwollmanRule StJohns 1936 1941 - May Sun>=8 0:00 1:00 D 3192742SwollmanRule StJohns 1936 1941 - Oct Sun>=1 0:00 0 S 3202742Swollman# Shanks gives 1942 May 11 - 1945 Sep 30; go with Whitman. 3212742SwollmanRule StJohns 1942 only - Mar 1 0:00 1:00 D 3222742SwollmanRule StJohns 1942 only - Dec 31 0:00 0 S 3232742SwollmanRule StJohns 1943 only - May 30 0:00 1:00 D 3242742SwollmanRule StJohns 1943 only - Sep 5 0:00 0 S 3252742SwollmanRule StJohns 1944 only - Jul 10 0:00 1:00 D 3262742SwollmanRule StJohns 1944 only - Sep 2 0:00 0 S 3272742SwollmanRule StJohns 1945 only - Jan 1 0:00 1:00 D 3282742SwollmanRule StJohns 1945 only - Oct 7 2:00 0 S 3292742Swollman# For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives 3302742Swollman# Apr 30 - Sep 24; go with Shanks. 3312742SwollmanRule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D 3322742SwollmanRule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S 3332742SwollmanRule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D 3342742SwollmanRule StJohns 1951 1959 - Sep lastSun 2:00 0 S 3352742SwollmanRule StJohns 1960 max - Oct lastSun 2:00 0 S 3362742SwollmanRule StJohns 1987 only - Apr Sun>=1 2:00 1:00 D 3372742SwollmanRule StJohns 1988 only - Apr Sun>=1 2:00 2:00 D 3382742SwollmanRule StJohns 1989 max - Apr Sun>=1 2:00 1:00 D 3392742Swollman# St John's has an apostrophe, but Posix file names can't have apostrophes. 3402742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 3412742SwollmanZone America/St_Johns -3:30:52 - LMT 1884 3422742Swollman -3:31 StJohns N%sT 1935 Mar 30 3432742Swollman -3:30 StJohns N%sT 3442742Swollman 3452742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 3462742SwollmanRule Halifax 1902 only - Jun 15 0:00 0 S 3472742SwollmanRule Halifax 1916 only - Apr 1 0:00 1:00 D 3482742SwollmanRule Halifax 1916 only - Oct 1 0:00 0 S 3492742SwollmanRule Halifax 1918 only - Apr 14 2:00 1:00 D 3502742SwollmanRule Halifax 1918 only - Oct 31 2:00 0 S 3512742SwollmanRule Halifax 1920 only - May 9 0:00 1:00 D 3522742SwollmanRule Halifax 1920 only - Aug 29 0:00 0 S 3532742SwollmanRule Halifax 1921 only - May 6 0:00 1:00 D 3542742SwollmanRule Halifax 1921 1922 - Sep 5 0:00 0 S 3552742SwollmanRule Halifax 1922 only - Apr 30 0:00 1:00 D 3562742SwollmanRule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D 3572742SwollmanRule Halifax 1923 only - Sep 4 0:00 0 S 3582742SwollmanRule Halifax 1924 only - Sep 15 0:00 0 S 3592742SwollmanRule Halifax 1925 only - Sep 28 0:00 0 S 3602742SwollmanRule Halifax 1926 only - May 16 0:00 1:00 D 3612742SwollmanRule Halifax 1926 only - Sep 13 0:00 0 S 3622742SwollmanRule Halifax 1927 only - May 1 0:00 1:00 D 3632742SwollmanRule Halifax 1927 only - Sep 26 0:00 0 S 3642742SwollmanRule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D 3652742SwollmanRule Halifax 1928 only - Sep 9 0:00 0 S 3662742SwollmanRule Halifax 1929 only - Sep 3 0:00 0 S 3672742SwollmanRule Halifax 1930 only - Sep 15 0:00 0 S 3682742SwollmanRule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S 3692742SwollmanRule Halifax 1933 only - Apr 30 0:00 1:00 D 3702742SwollmanRule Halifax 1933 only - Oct 2 0:00 0 S 3712742SwollmanRule Halifax 1934 only - May 20 0:00 1:00 D 3722742SwollmanRule Halifax 1934 only - Sep 16 0:00 0 S 3732742SwollmanRule Halifax 1935 only - Jun 2 0:00 1:00 D 3742742SwollmanRule Halifax 1935 only - Sep 30 0:00 0 S 3752742SwollmanRule Halifax 1936 only - Jun 1 0:00 1:00 D 3762742SwollmanRule Halifax 1936 only - Sep 14 0:00 0 S 3772742SwollmanRule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D 3782742SwollmanRule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S 3792742SwollmanRule Halifax 1939 only - May 28 0:00 1:00 D 3802742SwollmanRule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D 3812742SwollmanRule Halifax 1942 only - Feb 9 2:00 1:00 D 3822742SwollmanRule Halifax 1945 1959 - Sep lastSun 2:00 0 S 3832742SwollmanRule Halifax 1946 1959 - Apr lastSun 2:00 1:00 D 3842742SwollmanRule Halifax 1962 1986 - Apr lastSun 2:00 1:00 D 3852742SwollmanRule Halifax 1962 max - Oct lastSun 2:00 0 S 3862742SwollmanRule Halifax 1987 max - Apr Sun>=1 2:00 1:00 D 3872742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 3882742SwollmanZone America/Halifax -4:14:24 - LMT 1902 Jun 15 3892742Swollman -4:00 Halifax A%sT 3902742Swollman 3912742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 3922742SwollmanRule Mont 1884 only - Jan 1 0:00 0 S 3932742SwollmanRule Mont 1917 only - Mar 25 2:00 1:00 D 3942742SwollmanRule Mont 1917 only - Apr 24 0:00 0 S 3952742SwollmanRule Mont 1918 only - Apr 14 2:00 1:00 D 3962742SwollmanRule Mont 1918 only - Oct 31 2:00 0 S 3972742SwollmanRule Mont 1919 only - Mar 31 2:30 1:00 D 3982742SwollmanRule Mont 1919 only - Oct 25 2:30 0 S 3992742SwollmanRule Mont 1920 only - May 2 2:30 1:00 D 4002742SwollmanRule Mont 1920 only - Oct 3 2:30 0 S 4012742SwollmanRule Mont 1921 only - May 1 2:00 1:00 D 4022742SwollmanRule Mont 1921 only - Oct 2 2:30 0 S 4032742SwollmanRule Mont 1922 only - Apr 30 2:00 1:00 D 4042742SwollmanRule Mont 1922 only - Oct 1 2:30 0 S 4052742SwollmanRule Mont 1924 only - May 17 2:00 1:00 D 4062742SwollmanRule Mont 1924 1926 - Sep lastSun 2:30 0 S 4072742SwollmanRule Mont 1925 1926 - May Sun>=1 2:00 1:00 D 4082742SwollmanRule Mont 1927 only - May 1 0:00 1:00 D 4092742SwollmanRule Mont 1927 1932 - Sep Sun>=25 0:00 0 S 4102742SwollmanRule Mont 1928 1931 - Apr Sun>=25 0:00 1:00 D 4112742SwollmanRule Mont 1932 only - May 1 0:00 1:00 D 4122742SwollmanRule Mont 1933 1940 - Apr Sun>=24 0:00 1:00 D 4132742SwollmanRule Mont 1933 only - Oct 1 0:00 0 S 4142742SwollmanRule Mont 1934 1939 - Sep Sun>=24 0:00 0 S 4152742SwollmanRule Mont 1945 1948 - Sep lastSun 2:00 0 S 4162742SwollmanRule Mont 1946 1986 - Apr lastSun 2:00 1:00 D 4172742SwollmanRule Mont 1949 1950 - Oct lastSun 2:00 0 S 4182742SwollmanRule Mont 1951 1956 - Sep lastSun 2:00 0 S 4192742SwollmanRule Mont 1957 max - Oct lastSun 2:00 0 S 4202742SwollmanRule Mont 1987 max - Apr Sun>=1 2:00 1:00 D 4212742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 4222742SwollmanZone America/Montreal -4:54:16 - LMT 1884 4232742Swollman -5:00 Mont E%sT 4242742Swollman 4252742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 4262742SwollmanRule Winn 1887 only - Jul 16 0:00 0 S 4272742SwollmanRule Winn 1916 only - Apr 23 0:00 1:00 D 4282742SwollmanRule Winn 1916 only - Sep 17 0:00 0 S 4292742SwollmanRule Winn 1918 only - Apr 14 2:00 1:00 D 4302742SwollmanRule Winn 1918 only - Oct 31 2:00 0 S 4312742SwollmanRule Winn 1937 only - May 16 2:00 1:00 D 4322742SwollmanRule Winn 1937 only - Sep 23 2:00 0 S 4332742SwollmanRule Winn 1942 only - Feb 9 2:00 1:00 D 4342742SwollmanRule Winn 1945 only - Sep lastSun 2:00 0 S 4352742SwollmanRule Winn 1946 only - May 12 2:00 1:00 D 4362742SwollmanRule Winn 1946 only - Oct 13 2:00 0 S 4372742SwollmanRule Winn 1947 1949 - Apr lastSun 2:00 1:00 D 4382742SwollmanRule Winn 1947 1958 - Sep lastSun 2:00 0 S 4392742SwollmanRule Winn 1948 only - May 1 2:00 1:00 D 4402742SwollmanRule Winn 1948 1960 - Apr lastSun 2:00 1:00 D 4412742SwollmanRule Winn 1959 only - Oct lastSun 2:00 0 S 4422742SwollmanRule Winn 1960 only - Sep lastSun 2:00 0 S 4432742SwollmanRule Winn 1963 only - Apr lastSun 2:00 1:00 D 4442742SwollmanRule Winn 1963 only - Sep lastSun 2:00 0 S 4452742SwollmanRule Winn 1966 1986 - Apr lastSun 2:00 1:00 D 4462742SwollmanRule Winn 1966 max - Sep lastSun 2:00 0 S 4472742SwollmanRule Winn 1987 max - Apr Sun>=1 2:00 1:00 D 4482742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 4492742SwollmanZone America/Winnipeg -6:28:36 - LMT 1887 Jul 16 4502742Swollman -6:00 Winn C%sT 4512742Swollman 4522742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 4532742SwollmanRule Regina 1905 only - Sep 1 0:00 0 S 4542742SwollmanRule Regina 1918 only - Apr 14 2:00 1:00 D 4552742SwollmanRule Regina 1918 only - Oct 31 2:00 0 S 4562742SwollmanRule Regina 1930 1934 - May Sun>=1 0:00 1:00 D 4572742SwollmanRule Regina 1930 1934 - Oct Sun>=1 0:00 0 S 4582742SwollmanRule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D 4592742SwollmanRule Regina 1937 only - Oct Sun>=8 0:00 0 S 4602742SwollmanRule Regina 1938 only - Oct Sun>=1 0:00 0 S 4612742SwollmanRule Regina 1939 1941 - Oct Sun>=8 0:00 0 S 4622742SwollmanRule Regina 1942 only - Feb 9 2:00 1:00 D 4632742SwollmanRule Regina 1945 only - Sep lastSun 2:00 0 S 4642742SwollmanRule Regina 1946 only - Apr 14 2:00 1:00 D 4652742SwollmanRule Regina 1946 only - Oct 13 2:00 0 S 4662742SwollmanRule Regina 1947 1960 - Apr lastSun 2:00 1:00 D 4672742SwollmanRule Regina 1947 1959 - Sep lastSun 2:00 0 S 4682742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 4692742SwollmanZone America/Regina -6:58:36 - LMT 1905 Sep 4702742Swollman -7:00 Regina M%sT 1966 Apr 15 4712742Swollman -6:00 - CST 4722742Swollman 4732742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 4742742SwollmanRule Edm 1906 only - Sep 1 0:00 0 S 4752742SwollmanRule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D 4762742SwollmanRule Edm 1918 only - Oct 31 2:00 0 S 4772742SwollmanRule Edm 1919 only - May 27 2:00 0 S 4782742SwollmanRule Edm 1920 1923 - Apr lastSun 2:00 1:00 D 4792742SwollmanRule Edm 1920 only - Oct lastSun 2:00 0 S 4802742SwollmanRule Edm 1921 1923 - Sep lastSun 2:00 0 S 4812742SwollmanRule Edm 1942 only - Feb 9 2:00 1:00 D 4822742SwollmanRule Edm 1945 only - Sep lastSun 2:00 0 S 4832742SwollmanRule Edm 1947 only - Apr lastSun 2:00 1:00 D 4842742SwollmanRule Edm 1947 only - Sep lastSun 2:00 0 S 4852742SwollmanRule Edm 1967 only - Apr lastSun 2:00 1:00 D 4862742SwollmanRule Edm 1967 only - Oct lastSun 2:00 0 S 4872742SwollmanRule Edm 1969 only - Apr lastSun 2:00 1:00 D 4882742SwollmanRule Edm 1969 only - Oct lastSun 2:00 0 S 4892742SwollmanRule Edm 1972 1986 - Apr lastSun 2:00 1:00 D 4902742SwollmanRule Edm 1972 max - Oct lastSun 2:00 0 S 4912742SwollmanRule Edm 1987 max - Apr Sun>=1 2:00 1:00 D 4922742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 4932742SwollmanZone America/Edmonton -7:33:52 - LMT 1906 Sep 4942742Swollman -7:00 Edm M%sT 4952742Swollman 4962742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 4972742SwollmanRule Vanc 1884 only - Jan 1 0:00 0 S 4982742SwollmanRule Vanc 1918 only - Apr 14 2:00 1:00 D 4992742SwollmanRule Vanc 1918 only - Oct 31 2:00 0 S 5002742SwollmanRule Vanc 1942 only - Feb 9 2:00 1:00 D 5012742SwollmanRule Vanc 1945 only - Sep 30 2:00 0 S 5022742SwollmanRule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D 5032742SwollmanRule Vanc 1946 only - Oct 13 2:00 0 S 5042742SwollmanRule Vanc 1947 1961 - Sep lastSun 2:00 0 S 5052742SwollmanRule Vanc 1962 max - Oct lastSun 2:00 0 S 5062742SwollmanRule Vanc 1987 max - Apr Sun>=1 2:00 1:00 D 5072742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 5082742SwollmanZone America/Vancouver -8:12:28 - LMT 1884 5092742Swollman -8:00 Vanc P%sT 5102742Swollman 5112742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 5122742SwollmanRule Yukon 1900 only - Jan 1 0:00 0 S 5132742SwollmanRule Yukon 1918 only - Apr 14 2:00 1:00 D 5142742SwollmanRule Yukon 1918 only - Oct 27 2:00 0 S 5152742SwollmanRule Yukon 1919 only - May 25 2:00 1:00 D 5162742SwollmanRule Yukon 1919 only - Nov 1 0:00 0 S 5172742SwollmanRule Yukon 1942 only - Feb 9 2:00 1:00 D 5182742SwollmanRule Yukon 1965 only - Apr 25 0:00 1:00 D 5192742SwollmanRule Yukon 1965 only - Oct 31 2:00 0 S 5202742SwollmanRule Yukon 1980 1986 - Apr lastSun 2:00 1:00 D 5212742SwollmanRule Yukon 1980 max - Oct lastSun 2:00 0 S 5222742SwollmanRule Yukon 1987 max - Apr Sun>=1 2:00 1:00 D 5232742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 5242742SwollmanZone America/Whitehorse -9:00:12 - LMT 1900 Aug 20 5252742Swollman -9:00 Yukon Y%sT 1966 Jul 5262742Swollman -8:00 Yukon P%sT 5272742Swollman# Parts of Yukon (e.g. Dawson) didn't switch to -8:00 until 1973 Oct 28. 5282742Swollman 5292742Swollman############################################################################### 5302742Swollman 5312742Swollman# Mexico 5322742Swollman 5332742Swollman# From Guy Harris: 5342742Swollman# Rules are from the Official Airline Guide, Worldwide Edition, for 1987. 5352742Swollman# Rules prior to 1987 are unknown. 5362742Swollman# The comments in the OAG say "Only Ensenada, Mexicale, San Felipe and Tijuana 5372742Swollman# observe DST." This is presumably Baja California Norte, above 28th parallel, 5382742Swollman# as listed there; Mexico/BajaSur is for "Baja California Sur and N. Pacific 5392742Swollman# Coast (States of Sinaloa and Sonora)." 5402742Swollman 5412742Swollman# From Bob Devine (January 28, 1988): 5422742Swollman# The Federal District (where Mexico City is) has observed [DST] several 5432742Swollman# times but not recently. 5442742Swollman# 5452742Swollman# I don't where to drawn the line in the North Baja area. 28th latitude 5462742Swollman# sounds good -- but it may be higher (how far [d]o radio stations from 5472742Swollman# San Diego affect culture?). 5482742Swollman# 5492742Swollman# The dates of DST probably go back to 1981. The rules are the same as 5502742Swollman# US's. This is going to be a headache for US presidential electi[o]n years! 5512742Swollman 5522742Swollman# From Arthur David Olson (February 13, 1988) 5532742Swollman# Since the 1981 starting date is only "probable," we'll keep the 1987 5542742Swollman# starting date below. 5552742Swollman 5562742Swollman# From U. S. Naval Observatory (January 19, 1989): 5572742Swollman# MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND 5582742Swollman# MEXICO BAJA CAL N N. PACIFIC COAST (STATES 5592742Swollman# MEXICO BAJA CAL N OF SINALOA AND SONORA) 5602742Swollman# MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3 5612742Swollman# MEXICO BAJA CAL N - OCT 29 5622742Swollman# MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3 5632742Swollman# MEXICO BAJA CAL N - 0CT 29 5642742Swollman# MEXICO 6 H BEHIND UTC STATES OF DURANGO, 5652742Swollman# MEXICO COAHUILA, NUEVO LEON, 5662742Swollman# MEXICO TAMAULIPAS 5672742Swollman# MEXICO 5 H BEHIND UTC STATES OF DURANGO, 5682742Swollman# MEXICO COAHUILA, NUEVO LEON, 5692742Swollman# MEXICO TAMAULIPAS APR 3 - OCT 29 5702742Swollman# MEXICO 6 H BEHIND UTC GENERAL MEXICO, STATES OF 5712742Swollman# MEXICO CAMPECHE, QUINTANA ROO AND 5722742Swollman# MEXICO YUCATAN 5732742Swollman 5742742Swollman# From Arthur David Olson (January 21, 1989): 5752742Swollman# April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989. Ahem. 5762742Swollman# USNO claims there should be four Mexican zones rather than three: 5772742Swollman# a zone that's GMT-8 with DST; a zone that's always GMT-7; 5782742Swollman# a zone that's GMT-6 with DST; and a zone that's always GMT-6. 5792742Swollman 5802742Swollman# From Paul Eggert <eggert@twinsun.com> (November 18, 1993): 5812742Swollman# Shanks also says there are four zones, but disagrees about the fourth. 5822742Swollman# Instead of GMT-6 with DST, he says there's GMT-8 without DST. 5832742Swollman 5842742Swollman# From Shanks (1991): 5852742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 5862742SwollmanRule Mexico 1922 only - Jan 1 0:00 0 S 5872742SwollmanRule Mexico 1939 only - Feb 5 0:00 1:00 D 5882742SwollmanRule Mexico 1939 only - Jun 25 0:00 0 S 5892742SwollmanRule Mexico 1940 only - Dec 9 0:00 1:00 D 5902742SwollmanRule Mexico 1941 only - Apr 1 0:00 0 S 5912742SwollmanRule Mexico 1943 only - Dec 16 0:00 1:00 D 5922742SwollmanRule Mexico 1944 only - May 1 0:00 0 S 5932742SwollmanRule Mexico 1950 only - Feb 12 0:00 1:00 D 5942742SwollmanRule Mexico 1950 only - Jul 30 0:00 0 S 5952742SwollmanRule BajaN 1950 1966 - Apr lastSun 2:00 1:00 D 5962742SwollmanRule BajaN 1950 1961 - Sep lastSun 2:00 0 S 5972742SwollmanRule BajaN 1961 1966 - Oct lastSun 2:00 0 S 5982742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 5992742SwollmanZone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 0:23:24 6002742Swollman -7:00 - MST 1927 Jun 10 23:00 6012742Swollman -6:00 - CST 1930 Nov 15 6022742Swollman -7:00 - MST 1931 May 1 23:00 6032742Swollman -6:00 - CST 1931 Oct 6042742Swollman -7:00 - MST 1932 Mar 30 23:00 6052742Swollman -6:00 Mexico C%sT 6062742SwollmanZone America/Mazatlan -7:05:40 - LMT 1921 Dec 31 23:54:20 6072742Swollman -7:00 - MST 1927 Jun 10 23:00 6082742Swollman -6:00 - CST 1930 Nov 15 6092742Swollman -7:00 - MST 1931 May 1 23:00 6102742Swollman -6:00 - CST 1931 Oct 6112742Swollman -7:00 - MST 1932 Mar 30 23:00 6122742Swollman -6:00 - CST 1942 Apr 6132742Swollman -7:00 - MST 1949 Jan 14 6142742Swollman -8:00 - PST 1970 6152742Swollman -7:00 - MST 6162742SwollmanZone America/Tijuana -7:48:04 - LMT 1922 Jan 1 0:11:56 6172742Swollman -8:00 - PST 1927 Jun 10 23:00 6182742Swollman -7:00 - MST 1930 Nov 16 6192742Swollman -8:00 - PST 1942 Apr 6202742Swollman -7:00 - MST 1949 Jan 14 6212742Swollman -8:00 BajaN P%sT 1967 Apr lastSun 2:00 6222742Swollman -8:00 US P%sT 6232742SwollmanZone America/Ensenada -7:46:28 - LMT 1922 Jan 1 0:13:32 6242742Swollman -8:00 - PST 1927 Jun 10 23:00 6252742Swollman -7:00 - MST 1930 Nov 16 6262742Swollman -8:00 - PST 1942 Apr 6272742Swollman -7:00 - MST 1949 Jan 14 6282742Swollman -8:00 - PST 6292742Swollman# 6302742Swollman# Revillagigedo Is 6312742Swollman# no information 6322742Swollman 6332742Swollman############################################################################### 6342742Swollman 6352742Swollman# Anguilla 6362742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6372742SwollmanZone America/Anguilla -4:12:16 - LMT 1912 Mar 2 6382742Swollman -4:00 - AST 6392742Swollman 6402742Swollman# Antigua and Barbuda 6412742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6422742SwollmanZone America/Antigua -4:07:12 - LMT 1912 Mar 2 6432742Swollman -5:00 - EST 1951 6442742Swollman -4:00 - AST 6452742Swollman 6462742Swollman# Bahamas 6472742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 6482742SwollmanRule Bahamas 1912 only - Mar 2 0:00 0 S 6492742SwollmanRule Bahamas 1964 max - Oct lastSun 2:00 0 S 6502742SwollmanRule Bahamas 1964 1986 - Apr lastSun 2:00 1:00 D 6512742SwollmanRule Bahamas 1987 max - Apr Sun>=1 2:00 1:00 D 6522742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6532742SwollmanZone America/Nassau -5:09:24 - LMT 1912 Mar 2 6542742Swollman -5:00 Bahamas E%sT 6552742Swollman 6562742Swollman# Barbados 6572742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 6582742SwollmanRule Barb 1932 only - Jan 1 0:00 0 S 6592742SwollmanRule Barb 1977 only - Jun 12 2:00 1:00 D 6602742SwollmanRule Barb 1977 1978 - Oct Sun>=1 2:00 0 S 6612742SwollmanRule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D 6622742SwollmanRule Barb 1979 only - Sep 30 2:00 0 S 6632742SwollmanRule Barb 1980 only - Sep 25 2:00 0 S 6642742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6652742SwollmanZone America/Barbados -3:58:28 - LMT 1924 # Bridgetown 6662742Swollman -3:58 - BMT 1932 # Bridgetown Mean Time 6672742Swollman -4:00 Barb A%sT 6682742Swollman 6692742Swollman# Belize 6702742Swollman# Whitman entirely disagrees with Shanks; go with Shanks. 6712742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 6722742SwollmanRule Belize 1912 only - Apr 1 0:00 0 S 6732742SwollmanRule Belize 1918 1942 - Oct Sun>=2 0:00 0:30 HD 6742742SwollmanRule Belize 1919 1943 - Feb Sun>=9 0:00 0 S 6752742SwollmanRule Belize 1973 only - Dec 5 0:00 1:00 D 6762742SwollmanRule Belize 1974 only - Feb 9 0:00 0 S 6772742SwollmanRule Belize 1982 only - Dec 18 0:00 1:00 D 6782742SwollmanRule Belize 1983 only - Feb 12 0:00 0 S 6792742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6802742SwollmanZone America/Belize -5:52:48 - LMT 1912 Apr 6812742Swollman -6:00 Belize C%sT 6822742Swollman 6832742Swollman# Bermuda 6842742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6852742SwollmanZone Atlantic/Bermuda -4:19:04 - LMT 1930 Jan 1 2:00 # Hamilton 6862742Swollman -4:00 - AST 1974 Apr 28 2:00 6872742Swollman -4:00 Bahamas A%sT 6882742Swollman 6892742Swollman# Cayman Is 6902742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 6912742SwollmanZone America/Cayman -5:25:32 - LMT 1890 # Georgetown 6922742Swollman -5:07 - KMT 1912 Feb # Kingston Mean Time 6932742Swollman -5:00 - EST 6942742Swollman 6952742Swollman# Clipperton 6962742Swollman# no information 6972742Swollman 6982742Swollman# Costa Rica 6992742Swollman# Shanks gives some very odd dates for 1991, and stops there. 7002742Swollman# For now, we won't guess further. 7012742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 7022742SwollmanRule CR 1921 only - Jan 15 0:00 0 S 7032742SwollmanRule CR 1979 1980 - Feb lastSun 0:00 1:00 D 7042742SwollmanRule CR 1979 1980 - Jun Sun>=1 0:00 0 S 7052742SwollmanRule CR 1991 only - Jan 19 0:00 1:00 D 7062742SwollmanRule CR 1991 only - Jul 1 0:00 0 S 7072742Swollman# There are too many San Joses elsewhere, so we'll use `Costa Rica'. 7082742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7092742SwollmanZone America/Costa_Rica -5:36:20 - LMT 1890 # San Jose 7102742Swollman -5:36 - SJMT 1921 Jan 15 # San Jose Mean Time 7112742Swollman -6:00 CR C%sT 7122742Swollman# Coco 7132742Swollman# no information; probably like America/Costa_Rica 7142742Swollman 7152742Swollman# Cuba 7162742Swollman 7172742Swollman# From Bob Devine (January 28, 1988): 7182742Swollman# . . .DST is from 2nd Sunday in May to 2nd Sunday in October since 1981. 7192742Swollman# Change at midnight. In 1979 & 1980, started at 3rd Sunday in March 7202742Swollman# (I think). 7212742Swollman 7222742Swollman# From U. S. Naval Observatory (January 19, 1989): 7232742Swollman# CUBA 5 H BEHIND UTC 7242742Swollman# CUBA 4 H BEHIND UTC MAR 20 - OCT 8 7252742Swollman 7262742Swollman# From Shanks (1991): 7272742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 7282742SwollmanRule Cuba 1925 only - Jul 19 12:00 0 S 7292742SwollmanRule Cuba 1928 only - Jun 10 0:00 1:00 D 7302742SwollmanRule Cuba 1928 only - Oct 10 0:00 0 S 7312742SwollmanRule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D 7322742SwollmanRule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S 7332742SwollmanRule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D 7342742SwollmanRule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S 7352742SwollmanRule Cuba 1965 only - Jun 1 0:00 1:00 D 7362742SwollmanRule Cuba 1965 only - Sep 30 0:00 0 S 7372742SwollmanRule Cuba 1966 only - May 29 0:00 1:00 D 7382742SwollmanRule Cuba 1966 only - Oct 2 0:00 0 S 7392742SwollmanRule Cuba 1967 only - Apr 8 0:00 1:00 D 7402742SwollmanRule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S 7412742SwollmanRule Cuba 1968 only - Apr 14 0:00 1:00 D 7422742SwollmanRule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D 7432742SwollmanRule Cuba 1969 1971 - Oct lastSun 0:00 0 S 7442742SwollmanRule Cuba 1972 1974 - Oct 8 0:00 0 S 7452742SwollmanRule Cuba 1975 1977 - Oct lastSun 0:00 0 S 7462742SwollmanRule Cuba 1978 only - May 7 0:00 1:00 D 7472742SwollmanRule Cuba 1978 1980 - Oct Sun>=8 0:00 0 S 7482742SwollmanRule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D 7492742SwollmanRule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D 7502742SwollmanRule Cuba 1981 max - Oct Sun>=8 0:00 0 S 7512742SwollmanRule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D 7522742SwollmanRule Cuba 1990 only - Apr 1 0:00 1:00 D 7532742SwollmanRule Cuba 1991 max - Mar Sun>=14 0:00 1:00 D 7542742Swollman 7552742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7562742SwollmanZone America/Havana -5:29:28 - LMT 1890 7572742Swollman -5:30 - HMT 1925 Jul 19 12:00 # Havana MT 7582742Swollman -5:00 Cuba C%sT 7592742Swollman 7602742Swollman# Dominica 7612742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7622742SwollmanZone America/Dominica -4:05:36 - LMT 1911 Jul 1 0:01 # Roseau 7632742Swollman -4:00 - AST 7642742Swollman 7652742Swollman# Dominican Republic 7662742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 7672742SwollmanRule DR 1933 only - Apr 1 12:00 0 S 7682742SwollmanRule DR 1966 only - Oct 30 0:00 1:00 D 7692742SwollmanRule DR 1967 only - Feb 28 0:00 0 S 7702742SwollmanRule DR 1969 1973 - Oct lastSun 0:00 0:30 HD 7712742SwollmanRule DR 1970 only - Feb 21 0:00 0 S 7722742SwollmanRule DR 1971 only - Jan 20 0:00 0 S 7732742SwollmanRule DR 1972 1974 - Jan 21 0:00 0 S 7742742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7752742SwollmanZone America/Santo_Domingo -4:39:36 - LMT 1890 7762742Swollman -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT 7772742Swollman -5:00 DR E%sT 1974 Oct 27 7782742Swollman -4:00 - AST 7792742Swollman 7802742Swollman# El Salvador 7812742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 7822742SwollmanRule Salv 1921 only - Jan 1 0:00 0 S 7832742SwollmanRule Salv 1987 1988 - May Sun>=1 0:00 1:00 D 7842742SwollmanRule Salv 1987 1988 - Sep lastSun 0:00 0 S 7852742Swollman# There are too many San Salvadors elsewhere, so we'll use `El Salvador'. 7862742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7872742SwollmanZone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador 7882742Swollman -6:00 Salv C%sT 7892742Swollman 7902742Swollman# Grenada 7912742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7922742SwollmanZone America/Grenada -4:07:00 - LMT 1911 Jul 7932742Swollman -4:00 - AST 7942742Swollman 7952742Swollman# Guadeloupe 7962742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 7972742SwollmanZone America/Guadeloupe -4:06:08 - LMT 1911 Jun 8 # Pointe a Pitre 7982742Swollman -4:00 - AST 7992742Swollman 8002742Swollman# Guatemala 8012742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 8022742SwollmanRule Guat 1918 only - Oct 5 0:00 0 S 8032742SwollmanRule Guat 1973 only - Nov 25 0:00 1:00 D 8042742SwollmanRule Guat 1974 only - Feb 24 0:00 0 S 8052742SwollmanRule Guat 1983 only - May 21 0:00 1:00 D 8062742SwollmanRule Guat 1983 only - Sep 22 0:00 0 S 8072742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8082742SwollmanZone America/Guatemala -6:02:04 - LMT 1918 Oct 5 8092742Swollman -6:00 Guat C%sT 8102742Swollman 8112742Swollman# Haiti 8122742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 8132742SwollmanRule Haiti 1917 only - Jan 24 12:00 0 S 8142742SwollmanRule Haiti 1983 only - May 8 0:00 1:00 D 8152742SwollmanRule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D 8162742SwollmanRule Haiti 1983 1987 - Oct lastSun 0:00 0 S 8172742SwollmanRule Haiti 1988 max - Apr Sun>=1 2:00 1:00 D 8182742SwollmanRule Haiti 1988 max - Oct lastSun 2:00 0 S 8192742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8202742SwollmanZone America/Port-au-Prince -4:49:20 - LMT 1890 8212742Swollman -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT 8222742Swollman -5:00 Haiti E%sT 8232742Swollman 8242742Swollman# Honduras 8252742Swollman# Shanks says 1921 Jan 1; go with Whitman's more precise Apr 1. 8262742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8272742SwollmanZone America/Tegucigalpa -5:48:52 - LMT 1921 Apr 8282742Swollman -6:00 Salv C%sT 8292742Swollman 8302742Swollman# Jamaica 8312742Swollman 8322742Swollman# From Bob Devine (January 28, 1988): 8332742Swollman# Follows US rules. 8342742Swollman 8352742Swollman# From U. S. Naval Observatory (January 19, 1989): 8362742Swollman# JAMAICA 5 H BEHIND UTC 8372742Swollman 8382742Swollman# From Shanks (1991): 8392742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8402742SwollmanZone America/Jamaica -5:07:12 - LMT 1890 # Kingston 8412742Swollman -5:07 - KMT 1912 Feb # Kingston Mean Time 8422742Swollman -5:00 - EST 1974 Jan 6 2:00 8432742Swollman -5:00 US E%sT 8442742Swollman 8452742Swollman# Martinique 8462742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8472742SwollmanZone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France 8482742Swollman -4:04 - FFMT 1911 May # Fort-de-France MT 8492742Swollman -4:00 - AST 1980 Apr 6 8502742Swollman -4:00 1:00 ADT 1980 Sep 28 8512742Swollman -4:00 - AST 8522742Swollman 8532742Swollman# Montserrat 8542742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8552742SwollmanZone America/Montserrat -4:08:52 - LMT 1911 Jul 1 0:01 # Plymouth 8562742Swollman -4:00 - AST 8572742Swollman 8582742Swollman# Nicaragua 8592742Swollman# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S 8602742SwollmanRule Nic 1975 only - Feb 16 0:00 0 S 8612742SwollmanRule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D 8622742SwollmanRule Nic 1979 1980 - Jun Mon>=23 0:00 0 S 8632742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8642742SwollmanZone America/Managua -5:45:08 - LMT 1890 8652742Swollman -5:45 - MMT 1934 Jun 23 # Managua Mean Time 8662742Swollman -6:00 - CST 1973 May 8672742Swollman -5:00 - EST 1975 Feb 16 8682742Swollman -6:00 Nic C%sT 8692742Swollman 8702742Swollman# Panama 8712742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8722742SwollmanZone America/Panama -5:18:08 - LMT 1890 8732742Swollman -5:20 - PMT 1908 Apr 22 # Panama Mean Time 8742742Swollman -5:00 - EST 8752742Swollman 8762742Swollman# Puerto Rico 8772742Swollman# There are too many San Juans elsewhere, so we'll use `Puerto_Rico'. 8782742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8792742SwollmanZone America/Puerto_Rico -4:24:28 - LMT 1899 Mar 28 12:00 # San Juan 8802742Swollman -4:00 - AST 1942 May 3 8812742Swollman -4:00 1:00 ADT 1945 Sep 30 2:00 8822742Swollman -4:00 - AST 8832742Swollman 8842742Swollman# St Kitts-Nevis 8852742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8862742SwollmanZone America/St_Kitts -4:10:52 - LMT 1912 Mar 2 # Basseterre 8872742Swollman -4:00 - AST 8882742Swollman 8892742Swollman# St Lucia 8902742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8912742SwollmanZone America/St_Lucia -4:04:00 - LMT 1890 # Castries 8922742Swollman -4:04 - CMT 1912 # Castries Mean Time 8932742Swollman -4:00 - AST 8942742Swollman 8952742Swollman# St Pierre and Miquelon 8962742Swollman# There are too many St Pierres elsewhere, so we'll use `Miquelon'. 8972742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 8982742SwollmanZone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre 8992742Swollman -4:00 - AST 1980 May 9002742Swollman -3:00 Mont SP%sT 9012742Swollman 9022742Swollman# St Vincent and the Grenadines 9032742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 9042742SwollmanZone America/St_Vincent -4:04:56 - LMT 1890 # Kingstown 9052742Swollman -4:05 - KMT 1912 # Kingstown Mean Time 9062742Swollman -4:00 - AST 9072742Swollman 9082742Swollman# Turks and Caicos 9092742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 9102742SwollmanZone America/Grand_Turk -4:44:32 - LMT 1890 9112742Swollman -5:07 - KMT 1912 Feb # Kingston Mean Time 9122742Swollman -5:00 - EST 1979 Apr 29 2:00 9132742Swollman -5:00 US E%sT 9142742Swollman 9152742Swollman# Virgin Is (British and US) 9162742Swollman# Zone NAME GMTOFF RULES FORMAT [UNTIL] 9172742SwollmanZone America/Virgin -4:19:44 - LMT 1911 Jul # Charlotte Amalie 9182742Swollman -4:00 - AST 919