# @(#)northamerica	7.11# 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> (August 17, 1994):# A reliable and entertaining source about time zones is# Derek Howse, Greenwich time and the discovery of the longitude,# Oxford University Press (1980).################################################################################ United States# 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, October 26, 1974# and Sunday, October 27, 1974 editions of the Washington Post.# From seismo!munnari!kre:# I recall also being told by someone once that Canada didn't have# the DST variations in 74/75 that the US did, but I am not nearly# sure enough of this to add anything.# From Arthur David Olson:# The above has been confirmed by Bob Devine; we'll go with it here.# 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/SRule	US	1918	1919	-	Mar	lastSun	2:00	1:00	DRule	US	1918	1919	-	Oct	lastSun	2:00	0	SRule	US	1942	only	-	Feb	9	2:00	1:00	W # WarRule	US	1945	only	-	Sep	30	2:00	0	SRule	US	1967	max	-	Oct	lastSun	2:00	0	SRule	US	1967	1973	-	Apr	lastSun	2:00	1:00	DRule	US	1974	only	-	Jan	6	2:00	1:00	DRule	US	1975	only	-	Feb	23	2:00	1:00	DRule	US	1976	1986	-	Apr	lastSun	2:00	1:00	DRule	US	1987	max	-	Apr	Sun>=1	2:00	1:00	D# From Bob Devine (January 28, 1988):# ...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 U. S. Naval Observatory (January 19, 1989):# 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 (January 21, 1989):# 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 (February 13, 1988):# 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 April 1, 1967 (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 April 1, 1967 until November 30, 1983 (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 November 30, 1983:#	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 <eggert@twinsun.com> (August 16, 1994):# Howse writes that Alaska switched from the Julian to the Gregorian calendar,# and from east-of-GMT to west-of-GMT days, in 1867 when the US purchased it# from Russia.  We don't have this data pinned down yet, though.# Easy stuff first--including Alaska, where we ignore history (since we# can't tell if we should give Yukon time or Alaska-Hawaii time for "old"# times).# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]Zone America/New_York	-5:00	US	E%sTZone America/Chicago	-6:00	US	C%sTZone America/Denver	-7:00	US	M%sTZone America/Los_Angeles -8:00	US	P%sTZone America/Anchorage	-9:00	US	AK%sT					# AK%sT is the abbreviation per USNO# Mainland US areas that are always Standard as of 1986.Zone America/Fort_Wayne -5:00	US	E%sT	1946			-5:00	-	EST	# Always EST as of 1986# From Arthur David Olson (October 28, 1991):# An article on page A3 of the Sunday, October 27, 1991 Washington Post# notes that Starke County switched from Central time to Eastern time as of# October 27, 1991.Zone America/Knox_IN	-6:00	US	C%sT	1991 Oct 27 2:00			-5:00	-	EST	# Always EST as of 1991Zone America/Phoenix	-7:00	US	M%sT	1946			-7:00	-	MST	# Always MST as of 1986# From Arthur David Olson (February 13, 1988):# However. . .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 Navajo# From Bob Devine (January 28, 1988):# Michigan didn't observe DST from 1968 to 1973.Zone America/Detroit	-5:00	US	E%sT	1968			-5:00	-	EST	1973			-5:00	US	E%sT# Samoa just changes names.  No DST, per Naval Observatory.## Howse writes that in 1879 the King of Samoa decided to change# ``the date in his kingdom from the Antipodean to the American system,# ordaining -- by a masterpiece of diplomatic flattery -- that# the Fourth of July should be celebrated twice in that year.''Zone Pacific/Samoa	 12:37:12 -	LMT	1879 Jul  5			-11:22:48 -	LMT	1911			-11:30	-	SST	1950			-11:00	-	NST	1967 Apr	# N=Nome			-11:00	-	BST	1983 Nov 30	# B=Bering			-11:00	-	SST			# S=SamoaZone Pacific/Midway	-11:49:28 -	LMT	1901			-11:00	-	NST	1967 Apr	# N=Nome			-11:00	-	BST	1983 Nov 30	# B=Bering			-11:00	-	SST			# S=Samoa# Aleutian has a name change.  DST, per Naval Observatory.Zone America/Atka	-10:00	US	AH%sT	1983 Nov 30			-10:00	US	HA%sT# From Arthur David Olson:# And then there's Hawaii.# DST was observed for one day in 1933;# Standard time was change by half an hour in 1947;# it's always standard as of 1986.Zone Pacific/Honolulu	-10:30	US	H%sT	1933 Apr 30 2:00			-10:30	1:00	HDT	1933 May  1 2:00			-10:30	US	H%sT	1947 Jun  8 2:00			-10:00	-	HST# Navassa# no information; probably like US/Eastern# Old names, for S5 users# Link	LINK-FROM		LINK-TOLink	America/New_York	EST5EDTLink	America/Chicago		CST6CDTLink	America/Denver		MST7MDTLink	America/Los_Angeles	PST8PDTLink	America/Fort_Wayne	ESTLink	America/Phoenix		MSTLink	Pacific/Honolulu	HST################################################################################# From Paul Eggert <eggert@twinsun.com> (November 18, 1993):# A good source for time zone historical data outside the U.S. is# Thomas G. Shanks, The International Atlas (3rd edition),# San Diego: ACS Publications, Inc. (1991).# Except where otherwise noted, it is the source for the data below.## 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.## I invented the abbreviation SPST for St Pierre Standard Time; SPDT likewise.# Corrections are welcome!## See the `africa' file for Zone naming conventions.# Canada# Canada is reportedly lots easier than the US--leastways since 1951.# I don't know what they did before then.# 4.3BSD claims that it's perfectly regular.# According to a posting in "comp.bugs.misc", "comp.unix.wizards", etc.# on February 8, 1987, by Dave Sherman of the Law Society of Upper Canada,# "...Canada (well, Ontario and at least some of the other provinces) are# adopting the new daylight savings time rules...".  We assume all of# Canada is doing so.# From Bob Devine (January 28, 1988):# All of Canada did have DST from your first rule except Saskatchewan.# Which parts did not observe DST is hard to pinpoint but most of the# province follows the rules.# NOTE: those that didn't have DST for that rule, also# probably did not have it for several years previous.# From U. S. Naval Observatory (January 19, 1989):# CANADA   NEW FDL    3.5H BEHIND UTC    ST.JOHN'S# CANADA   NEW FDL    1.5H BEHIND UTC    APR 3 - OCT 29# CANADA   ATLANTIC   4 H  BEHIND UTC    HALIFAX# CANADA   ATLANTIC   3 H  BEHIND UTC    APR 3 - OCT 29# CANADA   EASTERN    5 H  BEHIND UTC    TORONTO, MONTREAL, OTTAWA# CANADA   EASTERN    4 H  BEHIND UTC    APR 3 - OCT 29# CANADA   CENTRAL    6 H  BEHIND UTC    REGINA, WINNIPEG# CANADA   CENTRAL    5 H  BEHIND UTC    APR 3 - OCT 29# CANADA   MOUNTAIN   7 H  BEHIND UTC    CALGARY, EDMONTON# CANADA   MOUNTAIN   6 H  BEHIND UTC    APR 3 - OCT 29# CANADA   PACIFIC    8 H  BEHIND UTC    VANCOUVER# CANADA   PACIFIC    7 H  BEHIND UTC    APR 3 - OCT 29# CANADA   YUKON      SAME AS PACIFIC    DAWSON# From Arthur David Olson (January 21, 1989):# April 3 fell on a Sunday in 1988; October 29 fell on a Sunday in 1989.  Ahem.# Note claim that there's double DST in Newfoundland and that Yukon should# be same as Pacific.# From W. Jones (jones@skdad.usask.ca) (November 6, 1992):# 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.## Here's how I would summarize things.  Establish a "Saskatchewan" CST# time zone, and note that it officially exists as of 15 April 1966.  Any# current exceptions can put themselves in the "Mountain" zone, since# those are the rules they follow.  Any past exceptions can be forgotten,# since that's what those who live here have done.# From Arthur David Olson (November 21, 1992):# East-Saskatchewan kept to avoid problems for folks using that zone by name;# plain Saskatchewan added.# From Shanks (1991):# Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/SRule	StJohns	1884	only	-	Jan	 1	0:00	0	S