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-rw-r--r--timezone/northamerica614
1 files changed, 198 insertions, 416 deletions
diff --git a/timezone/northamerica b/timezone/northamerica
index 3d80c5e3c2..73e2470e0b 100644
--- a/timezone/northamerica
+++ b/timezone/northamerica
@@ -1,4 +1,4 @@
-# @(#)northamerica	8.10
+# @(#)northamerica	8.1
 # <pre>
 
 # also includes Central America and the Caribbean
@@ -30,12 +30,12 @@
 # That 1883 transition occurred at 12:00 new time, not at 12:00 old time.
 # See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005).
 
-# From Paul Eggert (2006-03-22):
+# From Paul Eggert (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 most of the pre-1991 US entries below.
+# It is the source for most of the pre-1991 US and Puerto Rico entries below.
 
 # From Paul Eggert (2001-03-06):
 # Daylight Saving Time was first suggested as a joke by Benjamin Franklin
@@ -229,7 +229,7 @@ Zone	PST8PDT		 -8:00	US	P%sT
 # Public law 106-564 (2000-12-23) introduced the abbreviation
 # "Chamorro Standard Time" for time in Guam and the Northern Marianas.
 # See the file "australasia".
-
+ 
 # From Arthur David Olson, 2005-08-09
 # The following was signed into law on 2005-08-08.
 #
@@ -274,7 +274,7 @@ Zone	PST8PDT		 -8:00	US	P%sT
 # set their watches and clocks on Eastern time."  It quotes H.H. "Bubba"
 # Roberts, city administrator in Phenix City. as saying "We are in the Central
 # time zone, but we do go by the Eastern time zone because so many people work
-# in Columbus."
+# in Columbus." 
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER
 Rule	NYC	1920	only	-	Mar	lastSun	2:00	1:00	D
@@ -301,13 +301,6 @@ Zone America/New_York	-4:56:02 -	LMT	1883 Nov 18 12:03:58
 # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota,
 # western Tennessee, most of Texas, Wisconsin
 
-# From Larry M. Smith (2006-04-26) re Wisconsin:
-# http://www.legis.state.wi.us/statutes/Stat0175.pdf ...
-# is currently enforced at the 01:00 time of change.  Because the local
-# "bar time" in the state corresponds to 02:00, a number of citations
-# are issued for the "sale of class 'B' alcohol after prohibited
-# hours" within the deviated hour of this change every year....
-
 # 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
@@ -328,16 +321,14 @@ Zone America/Chicago	-5:50:36 -	LMT	1883 Nov 18 12:09:24
 Zone America/North_Dakota/Center -6:45:12 - LMT	1883 Nov 18 12:14:48
 			-7:00	US	M%sT	1992 Oct 25 02:00
 			-6:00	US	C%sT
-# Morton County, ND, switched from mountain to central time on
-# 2003-10-26, except for the area around Mandan which was already central time.
-# See <http://dmses.dot.gov/docimages/p63/135818.pdf>.
-# Officially this switch also included part of Sioux County, and
-# Jones, Mellette, and Todd Counties in South Dakota;
-# but in practice these other counties were already observing central time.
-# See <http://www.epa.gov/fedrgstr/EPA-IMPACT/2003/October/Day-28/i27056.htm>.
-Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 12:14:21
-			-7:00	US	M%sT	2003 Oct 26 02:00
-			-6:00	US	C%sT
+# From Paul Eggert (2006-01-20):
+# The following is not implemented yet.
+# What is the most populous city in that area?
+# From http://www.statoids.com/tus.html (2006-01-20):
+# 2003-10-26 02:00: All of Morton County, ND, and the part of Sioux
+# County, ND east of ND route 31 moved from MT to CT.  (The area
+# around Fort Yates in Sioux County and the area around Mandan in
+# Morton County were already in CT.)
 
 # US mountain time, represented by Denver
 #
@@ -416,8 +407,7 @@ Zone America/Yakutat	 14:41:05 -	LMT	1867 Oct 18
 Zone America/Anchorage	 14:00:24 -	LMT	1867 Oct 18
 			 -9:59:36 -	LMT	1900 Aug 20 12:00
 			-10:00	-	CAT	1942
-			-10:00	US	CAT/CAWT 1945 Aug 14 23:00u
-			-10:00	US	CAT/CAPT 1946 # Peace
+			-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
@@ -537,9 +527,9 @@ Zone America/Boise	-7:44:49 -	LMT	1883 Nov 18 12:15:11
 # 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> (2006-03-01)
+# </a> (2005-10-30)
 #
-# From Paul Eggert (2006-03-22):
+# From Paul Eggert (2006-01-20):
 # Since 1970, most of Indiana has been like America/Indiana/Indianapolis,
 # with the following exceptions:
 #
@@ -559,7 +549,6 @@ Zone America/Boise	-7:44:49 -	LMT	1883 Nov 18 12:15:11
 #
 # Shanks partitioned Indiana into 345 regions, each with its own time history,
 # and wrote ``Even newspaper reports present contradictory information.''
-# Those Hoosiers!  Such a flighty and changeable people!
 # Fortunately, most of the complexity occurred before our cutoff date of 1970.
 #
 # Other than Indianapolis, the Indiana place names are so nondescript
@@ -569,10 +558,8 @@ Zone America/Boise	-7:44:49 -	LMT	1883 Nov 18 12:15:11
 # From Paul Eggert (2005-08-16):
 # http://www.mccsc.edu/time.html says that Indiana will use DST starting 2006.
 
-# From Nathan Stratton Treadway (2006-03-30):
-# http://www.dot.gov/affairs/dot0406.htm [3705 B]
 # From Deborah Goldsmith (2006-01-18):
-# http://dmses.dot.gov/docimages/pdf95/382329_web.pdf [2.9 MB]
+# http://dmses.dot.gov/docimages/pdf95/382329_web.pdf
 # From Paul Eggert (2006-01-20):
 # It says "DOT is relocating the time zone boundary in Indiana to move Starke,
 # Pulaski, Knox, Daviess, Martin, Pike, Dubois, and Perry Counties from the
@@ -638,7 +625,7 @@ Zone America/Indiana/Vincennes -5:50:07 - LMT	1883 Nov 18 12:09:53
 			-5:00	US	E%sT	1971
 			-5:00	-	EST	2006 Apr  2 2:00
 			-6:00	US	C%sT
-#
+# 
 # Pike County, Indiana moved from central to eastern time in 1977,
 # then switched back in 2006.
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER
@@ -831,10 +818,10 @@ Zone America/Menominee	-5:50:27 -	LMT	1885 Sep 18 12:00
 ################################################################################
 
 
-# From Paul Eggert (2006-03-22):
-# A good source for time zone historical data outside the U.S. is
-# Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition),
-# San Diego: ACS Publications, Inc. (2003).
+# From Paul Eggert (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 writes that a good source
 # for recent time zone data is the International Air Transport
@@ -842,8 +829,8 @@ Zone America/Menominee	-5:50:27 -	LMT	1885 Sep 18 12:00
 # published semiannually.  Law sent in several helpful summaries
 # of the IATA's data after 1990.
 #
-# Except where otherwise noted, Shanks & Pottenger is the source for
-# entries through 1990, and IATA SSIM is the source for entries afterwards.
+# Except where otherwise noted, Shanks is the source for entries through 1990,
+# and IATA SSIM is the source for entries after 1990.
 #
 # Other sources occasionally used include:
 #
@@ -891,51 +878,9 @@ Zone America/Menominee	-5:50:27 -	LMT	1885 Sep 18 12:00
 # From Paul Eggert (1994-11-22):
 # Alas, this sort of thing must be handled by localization software.
 
-# Unless otherwise specified, the data for Canada are all from Shanks
-# & Pottenger.
-
-# From Chris Walton (2006-04-01):
-# The British Columbia government announced yesterday that it will
-# adjust daylight savings next year to align with changes in the
-# U.S. and the rest of Canada....
-# http://www2.news.gov.bc.ca/news_releases_2005-2009/2006AG0014-000330.htm
-
-# From Chris Walton (2006-04-25):
-# Daylight saving time will be extended by four weeks starting in 2007....
-# Here is a news release which was issued today by the Nova Scotia government:
-# http://www.gov.ns.ca/news/details.asp?id=20060425004
-
-# From Chris Walton (2006-06-26):
-# [For New Brunswick] the new legislation dictates that the time change is to
-# be done at 02:00 instead of 00:01.
-# http://www.gnb.ca/0062/acts/BBA-2006/Chap-19.pdf
-# ...
-# Manitoba has traditionally changed the clock every fall at 03:00.
-# As of 2006, the transition is to take place one hour earlier at 02:00.
-# http://web2.gov.mb.ca/laws/statutes/ccsm/o030e.php
-# ...
-# [Alberta, Ontario, Quebec] will follow US rules.
-# http://www.qp.gov.ab.ca/documents/Acts/2006CH03_UNPR.cfm?frm_isbn=0779744934
-# http://www.e-laws.gov.on.ca/DBLaws/Source/Regs/English/2006/R06111_e.htm
-# http://www.assnat.qc.ca/eng/37legislature2/Projets-loi/Publics/06-a002.htm
-# ...
-# P.E.I. will follow US rules.  The new legislation is not law yet.
-# It passed first reading on April 20....
-# http://www.assembly.pe.ca/bills/pdf_first/62/3/bill-101.pdf
-# ...
-# Province of Newfoundland and Labrador.... The change is being considered.
-# http://www.releases.gov.nl.ca/releases/2006/mpa/0331n01.htm
-# ...
-# N.W.T. will follow US rules.  Whoever maintains the government web site
-# does not seem to believe in bookmarks.  To see the news release, click the
-# following link and search for "Daylight Savings Time Change".  Press the
-# "Daylight Savings Time Change" link; it will fire off a popup using
-# JavaScript.
-# http://www.exec.gov.nt.ca/currentnews/currentPR.asp?mode=archive
-
-
-
-# From Paul Eggert (2006-04-25):
+# Unless otherwise specified, the data for Canada are all from Shanks.
+
+# From Paul Eggert (2005-12-21):
 # H. David Matthews and Mary Vincent's map
 # <a href="http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp">
 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
@@ -947,10 +892,25 @@ Zone America/Menominee	-5:50:27 -	LMT	1885 Sep 18 12:00
 # information about standard and daylight saving time zones in Canada.
 # </a> (updated periodically).
 # Its unofficial information is often taken from Matthews and Vincent.
-
-# From Paul Eggert (2006-06-27):
-# For now, assume all of DST-observing Canada will fall into line with the
-# new US DST rules,
+#
+# CBC News reported that Ontario and Manitoba have announced plans to
+# follow the US change, and that Nova Scotia is considering it; see
+# <http://www.cbc.ca/news/background/daylightsavingtime/> (2005-10-21).
+# CBC news also reported that Prince Edward Island is the first
+# province in Atlantic Canada to follow the US change, and that Quebec
+# had agreed; see <http://www.cbc.ca/pei/story/pe_daylight_20051207.html>
+# (2005-12-07).
+#
+# To reflect all this, the Canada and Winn rules have been adjusted to
+# agree with the 2007 US change.  This means we assume most of Canada
+# will fall into line.  However, Alberta, British Columbia,
+# Newfoundland, Northwest Territories, and Yukon already have separate
+# rules in our database, so for now we'll leave them alone, which
+# means that we currently assume these regions will not change their
+# rules and will disagree with the US starting in 2007.  This
+# assumption is probably incorrect, with the possible exception of
+# Newfoundland.  We plan to adjust the Edm, Vanc, StJohns, and NT_YK
+# rules as the corresponding provinces make their announcements.
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Canada	1918	only	-	Apr	14	2:00	1:00	D
@@ -965,7 +925,7 @@ Rule	Canada	2007	max	-	Mar	Sun>=8	2:00	1:00	D
 Rule	Canada	2007	max	-	Nov	Sun>=1	2:00	0	S
 
 
-# Newfoundland and Labrador
+# Newfoundland (and far southeast Labrador)
 
 # From Paul Eggert (2000-10-02):
 # Matthews and Vincent (1998) write that Labrador should use NST/NDT,
@@ -976,21 +936,20 @@ Rule	Canada	2007	max	-	Nov	Sun>=1	2:00	0	S
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	StJohns	1917	only	-	Apr	 8	2:00	1:00	D
 Rule	StJohns	1917	only	-	Sep	17	2:00	0	S
-# Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks & Pottenger.
+# 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 & Pottenger.
+# 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 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks &
-# Pottenger.
+# For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks.
 Rule	StJohns	1936	1941	-	May	Mon>=9	0:00	1:00	D
 Rule	StJohns	1936	1941	-	Oct	Mon>=2	0:00	0	S
 # Whitman gives the following transitions:
 # 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07
-# but go with Shanks & Pottenger and assume they used Canadian rules.
+# but go with Shanks and assume they used Canadian rules.
 # 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 & Pottenger.
+# 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
@@ -1000,12 +959,9 @@ Rule	StJohns	1960	1986	-	Oct	lastSun	2:00	0	S
 # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches
 # at 00:01 local time.  For now, assume it started in 1987.
 Rule	StJohns	1987	only	-	Apr	Sun>=1	0:01	1:00	D
-Rule	StJohns	1987	2006	-	Oct	lastSun	0:01	0	S
+Rule	StJohns	1987	max	-	Oct	lastSun	0:01	0	S
 Rule	StJohns	1988	only	-	Apr	Sun>=1	0:01	2:00	DD
-Rule	StJohns	1989	2006	-	Apr	Sun>=1	0:01	1:00	D
-Rule	StJohns	2007	max	-	Mar	Sun>=8	0:01	1:00	D
-Rule	StJohns	2007	max	-	Nov	Sun>=1	0:01	0	S
-#
+Rule	StJohns	1989	max	-	Apr	Sun>=1	0:01	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
@@ -1033,13 +989,12 @@ Zone America/Goose_Bay	-4:01:40 -	LMT	1884 # Happy Valley-Goose Bay
 
 # west Labrador, Nova Scotia, Prince Edward I
 
-# From Paul Eggert (2006-03-22):
-# Shanks & Pottenger write that since 1970 most of this region has been like
-# Halifax.  Many locales did not observe peacetime DST until 1972;
+# 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 & Pottenger also write 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.
+# 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
@@ -1105,7 +1060,10 @@ Zone America/Glace_Bay	-3:59:48 -	LMT	1902 Jun 15
 # <http://www.gnb.ca/0062/PDF-acts/t-06.pdf> says they change at 00:01, and
 # <http://www.canlii.org/nb/laws/sta/t-6/20030127/whole.html> makes it
 # clear that this has been the case since at least 1993.
-# For now, assume it started in 1993.
+# For now, assume it started in 1993.  The Office of the Premier announced
+# <http://www.gnb.ca/cnb/news/pre/2005e1737pr.htm> (2005-12-23)
+# that they will bring forward proposed amendments to harmonize with the US;
+# for now assume that this will happen, but they'll still switch at 00:01.
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Moncton	1933	1935	-	Jun	Sun>=8	1:00	1:00	D
@@ -1118,9 +1076,11 @@ Rule	Moncton	1940	only	-	May	19	1:00	1:00	D
 Rule	Moncton	1941	only	-	May	 4	1:00	1:00	D
 Rule	Moncton	1946	1972	-	Apr	lastSun	2:00	1:00	D
 Rule	Moncton	1946	1956	-	Sep	lastSun	2:00	0	S
-Rule	Moncton	1957	1972	-	Oct	lastSun	2:00	0	S
+Rule	Moncton	1956	1972	-	Oct	lastSun	2:00	0	S
 Rule	Moncton	1993	2006	-	Apr	Sun>=1	0:01	1:00	D
 Rule	Moncton	1993	2006	-	Oct	lastSun	0:01	0	S
+Rule	Moncton	2007	max	-	Mar	Sun>=8	0:01	1:00	D
+Rule	Moncton	2007	max	-	Nov	Sun>=1	0:01	0	S
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone America/Moncton	-4:19:08 -	LMT	1883 Dec  9
 			-5:00	-	EST	1902 Jun 15
@@ -1129,79 +1089,13 @@ Zone America/Moncton	-4:19:08 -	LMT	1883 Dec  9
 			-4:00	Canada	A%sT	1946
 			-4:00	Moncton	A%sT	1973
 			-4:00	Canada	A%sT	1993
-			-4:00	Moncton	A%sT	2007
-			-4:00	Canada	A%sT
+			-4:00	Moncton	A%sT
 
-# Quebec
-
-# From Paul Eggert (2006-07-09):
-# Shanks & Pottenger write that since 1970 most of Quebec has been
-# like Montreal.
-
-# From Paul Eggert (2006-06-27):
-# Matthews and Vincent (1998) also write that Quebec east of the -63
-# meridian is supposed to observe AST, but residents as far east as
-# Natashquan use EST/EDT, and residents east of Natashquan use AST.
-# In "Official time in Quebec" the Quebec department of justice writes in
-# http://www.justice.gouv.qc.ca/english/publications/generale/temps-regl-1-a.htm
-# that "The residents of the Municipality of the
-# Cote-Nord-du-Golfe-Saint-Laurent and the municipalities of Saint-Augustin,
-# Bonne-Esperance and Blanc-Sablon apply the Official Time Act as it is
-# written and use Atlantic standard time all year round. The same applies to
-# the residents of the Native facilities along the lower North Shore."
-# <http://www.assnat.qc.ca/eng/37legislature2/Projets-loi/Publics/06-a002.htm>
-# says this common practice was codified into law as of 2007.
-# For lack of better info, guess this practice began around 1970, contra to
-# Shanks & Pottenger who have this region observing AST/ADT.
+# Ontario, Quebec
 
-# 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	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	1922	-	Oct	Sun>=1	2:30	0	S
-Rule	Mont	1921	only	-	May	 1	2:00	1:00	D
-Rule	Mont	1922	only	-	Apr	30	2:00	1:00	D
-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
-# The 1927-to-1937 rules can be expressed more simply as
-# Rule	Mont	1927	1937	-	Apr	lastSat	24:00	1:00	D
-# Rule	Mont	1927	1937	-	Sep	lastSat	24:00	0	S
-# The rules below avoid use of 24:00
-# (which pre-1998 versions of zic cannot handle).
-Rule	Mont	1927	only	-	May	1	0:00	1:00	D
-Rule	Mont	1927	1932	-	Sep	lastSun	0:00	0	S
-Rule	Mont	1928	1931	-	Apr	lastSun	0:00	1:00	D
-Rule	Mont	1932	only	-	May	1	0:00	1:00	D
-Rule	Mont	1933	1940	-	Apr	lastSun	0:00	1:00	D
-Rule	Mont	1933	only	-	Oct	1	0:00	0	S
-Rule	Mont	1934	1939	-	Sep	lastSun	0:00	0	S
-Rule	Mont	1946	1973	-	Apr	lastSun	2:00	1:00	D
-Rule	Mont	1945	1948	-	Sep	lastSun	2:00	0	S
-Rule	Mont	1949	1950	-	Oct	lastSun	2:00	0	S
-Rule	Mont	1951	1956	-	Sep	lastSun	2:00	0	S
-Rule	Mont	1957	1973	-	Oct	lastSun	2:00	0	S
-
-# Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
-Zone America/Blanc-Sablon -3:48:28 -	LMT	1884
-			-4:00	Canada	A%sT	1970
-			-4:00	-	AST
-Zone America/Montreal	-4:54:16 -	LMT	1884
-			-5:00	Mont	E%sT	1918
-			-5:00	Canada	E%sT	1919
-			-5:00	Mont	E%sT	1942 Feb  9 2:00s
-			-5:00	Canada	E%sT	1946
-			-5:00	Mont	E%sT	1974
-			-5:00	Canada	E%sT
-
-
-# Ontario
-
-# From Paul Eggert (2006-07-09):
-# Shanks & Pottenger write that since 1970 most of Ontario has been like
-# Toronto.
+# From Paul Eggert (1996-06-12):
+# Shanks writes that since 1970 most of Ontario has been like Toronto,
+# and most of Quebec 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.
@@ -1231,46 +1125,50 @@ Zone America/Montreal	-4:54:16 -	LMT	1884
 # 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.
+
 # From Paul Eggert (2000-10-02):
 # Matthews and Vincent (1998) write that Atikokan, Pickle Lake, and
 # New Osnaburgh observe CST all year, that Big Trout Lake observes
 # CST/CDT, and that Upsala and Shebandowan observe EST/EDT, all in
 # violation of the official Ontario rules.
-#
-# From Paul Eggert (2006-07-09):
-# Chris Walton (2006-07-06) mentioned an article by Stephanie MacLellan in the
-# 2005-07-21 Chronicle-Journal, which said:
-#
-#	The clocks in Atikokan stay set on standard time year-round.
-#	This means they spend about half the time on central time and
-#	the other half on eastern time.
-#
-#	For the most part, the system works, Mayor Dennis Brown said.
-#
-#	"The majority of businesses in Atikokan deal more with Eastern
-#	Canada, but there are some that deal with Western Canada," he
-#	said.  "I don't see any changes happening here."
-#
-# Walton also writes "Supposedly Pickle Lake and Mishkeegogamang
-# [New Osnaburgh] follow the same practice."
-
-# From Garry McKinnon (2006-07-14) via Chris Walton:
-# I chatted with a member of my board who has an outstanding memory
-# and a long history in Atikokan (and in the telecom industry) and he
-# can say for certain that Atikokan has been practicing the current
-# time keeping since 1952, at least.
-
-# From Paul Eggert (2006-07-17):
-# Shanks & Pottenger say that Atikokan has agreed with Rainy River
-# ever since standard time was introduced, but the information from
-# McKinnon sounds more authoritative.  For now, assume that Atikokan
-# switched to EST immediately after WWII era daylight saving time
-# ended.  This matches the old (less-populous) America/Coral_Harbour
-# entry since our cutoff date of 1970, so we can move
-# America/Coral_Harbour to the 'backward' file.
+# They also write that Quebec east of the -63 meridian is supposed to
+# observe AST, but residents as far east as Natashquan use EST/EDT,
+# and residents east of Natashquan use AST.
+# We probably need Zones for far east Quebec and for Atikokan,
+# but we don't know when their practices started.
 
 # 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	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	1922	-	Oct	Sun>=1	2:30	0	S
+Rule	Mont	1921	only	-	May	 1	2:00	1:00	D
+Rule	Mont	1922	only	-	Apr	30	2:00	1:00	D
+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
+# The 1927-to-1937 rules can be expressed more simply as
+# Rule	Mont	1927	1937	-	Apr	lastSat	24:00	1:00	D
+# Rule	Mont	1927	1937	-	Sep	lastSat	24:00	0	S
+# The rules below avoid use of 24:00
+# (which pre-1998 versions of zic cannot handle).
+Rule	Mont	1927	only	-	May	1	0:00	1:00	D
+Rule	Mont	1927	1932	-	Sep	lastSun	0:00	0	S
+Rule	Mont	1928	1931	-	Apr	lastSun	0:00	1:00	D
+Rule	Mont	1932	only	-	May	1	0:00	1:00	D
+Rule	Mont	1933	1940	-	Apr	lastSun	0:00	1:00	D
+Rule	Mont	1933	only	-	Oct	1	0:00	0	S
+Rule	Mont	1934	1939	-	Sep	lastSun	0:00	0	S
+Rule	Mont	1946	1973	-	Apr	lastSun	2:00	1:00	D
+Rule	Mont	1945	1948	-	Sep	lastSun	2:00	0	S
+Rule	Mont	1949	1950	-	Oct	lastSun	2:00	0	S
+Rule	Mont	1951	1956	-	Sep	lastSun	2:00	0	S
+Rule	Mont	1957	1973	-	Oct	lastSun	2:00	0	S
+
 Rule	Toronto	1919	only	-	Mar	30	23:30	1:00	D
 Rule	Toronto	1919	only	-	Oct	26	0:00	0	S
 Rule	Toronto	1920	only	-	May	 2	2:00	1:00	D
@@ -1278,8 +1176,7 @@ Rule	Toronto	1920	only	-	Sep	26	0:00	0	S
 Rule	Toronto	1921	only	-	May	15	2:00	1:00	D
 Rule	Toronto	1921	only	-	Sep	15	2:00	0	S
 Rule	Toronto	1922	1923	-	May	Sun>=8	2:00	1:00	D
-# Shanks & Pottenger say 1923-09-19; assume it's a typo and that "-16"
-# was meant.
+# Shanks says 1923-09-19; assume it's a typo and that "-16" was meant.
 Rule	Toronto	1922	1926	-	Sep	Sun>=15	2:00	0	S
 Rule	Toronto	1924	1927	-	May	Sun>=1	2:00	1:00	D
 # The 1927-to-1939 rules can be expressed more simply as
@@ -1303,10 +1200,9 @@ Rule	Toronto	1949	only	-	Nov	lastSun	0:00	0	S
 Rule	Toronto	1950	1973	-	Apr	lastSun	2:00	1:00	D
 Rule	Toronto	1950	only	-	Nov	lastSun	2:00	0	S
 Rule	Toronto	1951	1956	-	Sep	lastSun	2:00	0	S
-# Shanks & Pottenger say Toronto ended DST a week early in 1971,
-# namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this
-# is wrong, and that he had confirmed it by checking the 1971-10-30
-# Toronto Star, which said that DST was ending 1971-10-31 as usual.
+# Shanks says Toronto ended DST a week early in 1971, namely on 1971-10-24,
+# but Mark Brader wrote (2003-05-31) that he checked the 1971-10-30 issue
+# of the Toronto Star, and it said that DST ended 1971-10-31 as usual.
 Rule	Toronto	1957	1973	-	Oct	lastSun	2:00	0	S
 
 # From Paul Eggert (2003-07-27):
@@ -1328,6 +1224,13 @@ Rule	Toronto	1957	1973	-	Oct	lastSun	2:00	0	S
 # months for the remainder of the war years.
 
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
+Zone America/Montreal	-4:54:16 -	LMT	1884
+			-5:00	Mont	E%sT	1918
+			-5:00	Canada	E%sT	1919
+			-5:00	Mont	E%sT	1942 Feb  9 2:00s
+			-5:00	Canada	E%sT	1946
+			-5:00	Mont	E%sT	1974
+			-5:00	Canada	E%sT
 Zone America/Toronto	-5:17:32 -	LMT	1895
 			-5:00	Canada	E%sT	1919
 			-5:00	Toronto	E%sT	1942 Feb  9 2:00s
@@ -1345,38 +1248,14 @@ Zone America/Nipigon	-5:53:04 -	LMT	1895
 			-5:00	Canada	E%sT	1940 Sep 29
 			-5:00	1:00	EDT	1942 Feb  9 2:00s
 			-5:00	Canada	E%sT
-Zone America/Rainy_River -6:18:16 -	LMT	1895
+Zone America/Rainy_River -6:17:56 -	LMT	1895
 			-6:00	Canada	C%sT	1940 Sep 29
 			-6:00	1:00	CDT	1942 Feb  9 2:00s
 			-6:00	Canada	C%sT
-Zone America/Atikokan	-6:06:28 -	LMT	1895
-			-6:00	Canada	C%sT	1940 Sep 29
-			-6:00	1:00	CDT	1942 Feb  9 2:00s
-			-6:00	Canada	C%sT	1945 Sep 30 2:00
-			-5:00	-	EST
 
 
 # Manitoba
 
-# From Rob Douglas (2006-04-06):
-# the old Manitoba Time Act - as amended by Bill 2, assented to
-# March 27, 1987 ... said ...
-# "between two o'clock Central Standard Time in the morning of
-# the first Sunday of April of each year and two o'clock Central
-# Standard Time in the morning of the last Sunday of October next
-# following, one hour in advance of Central Standard Time."...
-# I believe that the English legislation [of the old time act] had =
-# been assented to (March 22, 1967)....
-# Also, as far as I can tell, there was no order-in-council varying
-# the time of Daylight Saving Time for 2005 and so the provisions of
-# the 1987 version would apply - the changeover was at 2:00 Central
-# Standard Time (i.e. not until 3:00 Central Daylight Time).
-
-# From Paul Eggert (2006-04-10):
-# Shanks & Pottenger say Manitoba switched at 02:00 (not 02:00s)
-# starting 1966.  Since 02:00s is clearly correct for 1967 on, assume
-# it was also 02:00s in 1966.
-
 # 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
@@ -1399,13 +1278,18 @@ 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	2:00s	1:00	D
-Rule	Winn	1966	2005	-	Oct	lastSun	2:00s	0	S
-Rule	Winn	1987	2005	-	Apr	Sun>=1	2:00s	1:00	D
+Rule	Winn	1966	1986	-	Apr	lastSun	2:00	1:00	D
+Rule	Winn	1966	1986	-	Oct	lastSun	2:00	0	S
+Rule	Winn	1987	2006	-	Apr	Sun>=1	2:00s	1:00	D
+# From Paul Eggert (2000-10-02):
+# INMS (2000-09-12) says that, since 1988 at least, Manitoba switches from
+# DST at 03:00 local time.  For now, assume it started in 1987.
+Rule	Winn	1987	2006	-	Oct	lastSun	2:00s	0	S
+Rule	Winn	2007	max	-	Mar	Sun>=8	2:00s	1:00	D
+Rule	Winn	2007	max	-	Nov	Sun>=1	2:00s	0	S
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone America/Winnipeg	-6:28:36 -	LMT	1887 Jul 16
-			-6:00	Winn	C%sT	2006
-			-6:00	Canada	C%sT
+			-6:00	Winn	C%sT
 
 
 # Saskatchewan
@@ -1424,8 +1308,8 @@ Zone America/Winnipeg	-6:28:36 -	LMT	1887 Jul 16
 # Willett (1914-03) notes that DST "has been in operation ... in the
 # City of Moose Jaw, Saskatchewan, for one year."
 
-# From Paul Eggert (2006-03-22):
-# Shanks & Pottenger say that since 1970 this region has mostly been as Regina.
+# From Paul Eggert (2000-10-02):
+# 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.
 # Matthews and Vincent (1998) write that Denare Beach and Creighton
@@ -1457,11 +1341,6 @@ Zone America/Winnipeg	-6:28:36 -	LMT	1887 Jul 16
 # rules any more; all other districts appear to have used CST year round
 # since sometime in the 1960s.
 
-# From Chris Walton (2006-06-26):
-# The Saskatchewan time act which was last updated in 1996 is about 30 pages
-# long and rather painful to read.
-# http://www.qp.gov.sk.ca/documents/English/Statutes/Statutes/T14.pdf
-
 # 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
@@ -1516,18 +1395,17 @@ 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	2006	-	Oct	lastSun	2:00	0	S
+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	1987
-			-7:00	Canada	M%sT
+			-7:00	Edm	M%sT
 
 
 # British Columbia
 
-# From Paul Eggert (2006-03-22):
-# Shanks & Pottenger write that since 1970 most of this region has
-# been like Vancouver.
+# From Paul Eggert (2000-10-02):
+# Shanks writes that since 1970 most of this region has been like Vancouver.
 # Dawson Creek uses MST.  Much of east BC is like Edmonton.
 # Matthews and Vincent (1998) write that Creston is like Dawson Creek.
 
@@ -1540,11 +1418,11 @@ 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	2006	-	Oct	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	1987
-			-8:00	Canada	P%sT
+			-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
@@ -1553,7 +1431,7 @@ Zone America/Dawson_Creek -8:00:56 -	LMT	1884
 
 # Northwest Territories, Nunavut, Yukon
 
-# From Paul Eggert (2006-03-22):
+# From Paul Eggert (1999-10-29):
 # Dawson switched to PST in 1973.  Inuvik switched to MST in 1979.
 # Mathew Englander (1996-10-07) gives the following refs:
 #	* 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68,
@@ -1562,12 +1440,7 @@ Zone America/Dawson_Creek -8:00:56 -	LMT	1884
 #	* 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 & Pottenger say Yukon's 1973-10-28 switch was at 2:00; go
-# with Englander.
-# From Chris Walton (2006-06-26):
-# Here is a link to the old daylight saving portion of the interpretation
-# act which was last updated in 1987:
-# http://www.gov.yk.ca/legislation/regs/oic1987_056.pdf
+# 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.
@@ -1676,10 +1549,6 @@ Zone America/Dawson_Creek -8:00:56 -	LMT	1884
 # For lack of better information, assume that Southampton Island observed
 # daylight saving only during wartime.
 
-# From Chris Walton (2006-07-19):
-# The government of Yukon Territory ... recently announced it will extend
-# daylight saving in 2007....  http://www.gov.yk.ca/news/2006/06-164.html
-
 # 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
@@ -1691,8 +1560,8 @@ 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	2006	-	Oct	lastSun	2:00	0	S
-Rule	NT_YK	1987	2006	-	Apr	Sun>=1	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
@@ -1703,11 +1572,10 @@ 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	2000 Oct 29 2:00
 			-5:00	Canada	E%sT
-# Now subsumed by America/Atikokan.
-#Zone America/Coral_Harbour -5:32:40 -	LMT	1884
-#			-5:00	NT_YK	E%sT	1946
-#			-5:00	-	EST
-Zone America/Rankin_Inlet -6:08:20 -	LMT	1884
+Zone America/Coral_Harbour -5:32:40 -	LMT	1884
+			-5:00	NT_YK	E%sT	1946
+			-5:00	-	EST
+Zone America/Rankin_Inlet -6:08:40 -	LMT	1884
 			-6:00	NT_YK	C%sT	2000 Oct 29 2:00
 			-5:00	-	EST	2001 Apr  1 3:00
 			-6:00	Canada	C%sT
@@ -1718,20 +1586,16 @@ Zone America/Cambridge_Bay -7:00:20 -	LMT	1884
 			-6:00	-	CST	2001 Apr  1 3:00
 			-7:00	Canada	M%sT
 Zone America/Yellowknife -7:37:24 -	LMT	1884
-			-7:00	NT_YK	M%sT	1980
-			-7:00	Canada	M%sT
-Zone America/Inuvik	-8:54:52 -	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	1980
-			-7:00	Canada	M%sT
+			-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	1980
-			-8:00	Canada	P%sT
+			-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	1980
-			-8:00	Canada	P%sT
+			-8:00	NT_YK	P%sT
 
 
 ###############################################################################
@@ -1745,12 +1609,16 @@ Zone America/Dawson	-9:17:40 -	LMT	1900 Aug 20
 # history of Mexican local time (in Spanish)
 # </a>.
 #
-# Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC.
+# Here are the discrepancies between Shanks and the MLoC.
 # (In all cases we go with the MLoC.)
-# S&P report that Baja was at -8:00 in 1922/1923.
-# S&P say the 1930 transition in Baja was 1930-11-16.
-# S&P report no DST during summer 1931.
-# S&P report a transition at 1932-03-30 23:00, not 1932-04-01.
+# Shanks reports that Baja was at -8:00 in 1922/1923.
+# Shanks says the 1930 transition in Baja was 1930-11-16.
+# Shanks reports no DST during summer 1931.
+# Shanks reports a transition at 1932-03-30 23:00, not 1932-04-01.
+# Shanks does not report transitions for Baja in 1945 or 1948.
+# Shanks reports southern Mexico transitions on 1981-12-01, not 12-23.
+# Shanks says Quintana Roo switched to -6:00 on 1982-12-02, and to -5:00
+# on 1997-10-26 at 02:00.
 
 # From Gwillim Law (2001-02-20):
 # There are some other discrepancies between the Decrees page and the
@@ -1758,6 +1626,10 @@ Zone America/Dawson	-9:17:40 -	LMT	1900 Aug 20
 # the researchers who prepared the Decrees page failed to find some of
 # the relevant documents.
 
+# From Paul Eggert (2000-07-26):
+# Shanks gives 1942-04-01 instead of 1942-04-24, and omits the 1981
+# and 1988 DST experiments.  Go with spin.com.mx.
+
 # From Alan Perry (1996-02-15):
 # A guy from our Mexico subsidiary finally found the Presidential Decree
 # outlining the timezone changes in Mexico.
@@ -1957,8 +1829,7 @@ Zone America/Tijuana	-7:48:04 -	LMT	1922 Jan  1  0:11:56
 			-8:00	-	PST	1931 Apr  1
 			-8:00	1:00	PDT	1931 Sep 30
 			-8:00	-	PST	1942 Apr 24
-			-8:00	1:00	PWT	1945 Aug 14 23:00u
-			-8:00	1:00	PPT	1945 Nov 12 # Peace
+			-8:00	1:00	PWT	1945 Nov 12
 			-8:00	-	PST	1948 Apr  5
 			-8:00	1:00	PDT	1949 Jan 14
 			-8:00	-	PST	1954
@@ -1968,13 +1839,12 @@ Zone America/Tijuana	-7:48:04 -	LMT	1922 Jan  1  0:11:56
 			-8:00	Mexico	P%sT	2001
 			-8:00	US	P%sT	2002 Feb 20
 			-8:00	Mexico	P%sT
-# From Paul Eggert (2006-03-22):
+# From Paul Eggert (2001-03-05):
 # Formerly there was an America/Ensenada zone, which differed from
 # America/Tijuana only in that it did not observe DST from 1976
-# through 1995.  This was as per Shanks (1999).  But Shanks & Pottenger say
-# Ensenada did not observe DST from 1948 through 1975.  Guy Harris reports
+# through 1995.  This was as per Shanks.  However, Guy Harris reports
 # that the 1987 OAG says "Only Ensenada, Mexicale, San Felipe and
-# Tijuana observe DST," which agrees with Shanks & Pottenger but implies that
+# Tijuana observe DST," which contradicts Shanks but does imply that
 # DST-observance was a town-by-town matter back then.  This concerns
 # data after 1970 so most likely there should be at least one Zone
 # other than America/Tijuana for Baja, but it's not clear yet what its
@@ -2018,7 +1888,7 @@ Zone America/Barbados	-3:58:28 -	LMT	1924		# Bridgetown
 			-4:00	Barb	A%sT
 
 # Belize
-# Whitman entirely disagrees with Shanks; go with Shanks & Pottenger.
+# 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
@@ -2031,20 +1901,10 @@ Zone	America/Belize	-5:52:48 -	LMT	1912 Apr
 			-6:00	Belize	C%sT
 
 # Bermuda
-
-# From Dan Jones, reporting in The Royal Gazette (2006-06-26):
-
-# Next year, however, clocks in the US will go forward on the second Sunday
-# in March, until the first Sunday in November.  And, after the Time Zone
-# (Seasonal Variation) Bill 2006 was passed in the House of Assembly on
-# Friday, the same thing will happen in Bermuda.
-# http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135
-
 # 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	1976
-			-4:00	US	A%sT
+			-4:00	Bahamas	A%sT
 
 # Cayman Is
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
@@ -2057,8 +1917,7 @@ Zone	America/Cayman	-5:25:32 -	LMT	1890		# Georgetown
 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 & Pottenger.
+# 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'.
@@ -2084,26 +1943,18 @@ Zone America/Costa_Rica	-5:36:20 -	LMT	1890		# San Jose
 
 # From Evert van der Veer via Steffen Thorsen (2004-10-28):
 # Cuba is not going back to standard time this year.
-# From Paul Eggert (2006-03-22):
+# From Paul Eggert (2004-10-28):
 # http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html
 # says that it's due to a problem at the Antonio Guiteras
 # thermoelectric plant, and says "This October there will be no return
 # to normal hours (after daylight saving time)".
-# For now, let's assume that it's a temporary measure.
+# For now, let's assume that it's a one-year temporary measure.
 
 # From Carlos A. Carnero Delgado (2005-11-12):
 # This year (just like in 2004-2005) there's no change in time zone
 # adjustment in Cuba.  We will stay in daylight saving time:
 # http://www.granma.cu/espanol/2005/noviembre/mier9/horario.html
 
-# From Jesper Norgaard Welen (2006-10-21):
-# An article in GRANMA INTERNACIONAL claims that Cuba will end
-# the 3 years of permanent DST next weekend, see
-# http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html
-# "On Saturday night, October 28 going into Sunday, October 29, at 01:00,
-# watches should be set back one hour -- going back to 00:00 hours -- returning
-# to the normal schedule....
-
 # 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
@@ -2182,7 +2033,6 @@ Zone America/Santo_Domingo -4:39:36 -	LMT	1890
 			-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
@@ -2203,19 +2053,6 @@ Zone America/Guadeloupe	-4:06:08 -	LMT	1911 Jun 8	# Pointe a Pitre
 			-4:00	-	AST
 
 # Guatemala
-#
-# From Gwillim Law (2006-04-22), after a heads-up from Oscar van Vlijmen:
-# Diario Co Latino, at
-# http://www.diariocolatino.com/internacionales/detalles.asp?NewsID=8079,
-# says in an article dated 2006-04-19 that the Guatemalan government had
-# decided on that date to advance official time by 60 minutes, to lessen the
-# impact of the elevated cost of oil....  Daylight saving time will last from
-# 2006-04-29 24:00 (Guatemalan standard time) to 2006-09-30 (time unspecified).
-# From Paul Eggert (2006-06-22):
-# The Ministry of Energy and Mines, press release CP-15/2006
-# (2006-04-19), says DST ends at 24:00.  See
-# <http://www.sieca.org.gt/Sitio_publico/Energeticos/Doc/Medidas/Cambio_Horario_Nac_190406.pdf>.
-
 # 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
@@ -2223,8 +2060,6 @@ 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
-Rule	Guat	2006	only	-	Apr	30	0:00	1:00	D
-Rule	Guat	2006	only	-	Oct	 1	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
@@ -2249,67 +2084,26 @@ Zone America/Guatemala	-6:02:04 -	LMT	1918 Oct 5
 #   October 2005.
 #
 #  "Port-au-Prince, March 31, 2005"
-#
-# From Steffen Thorsen (2006-04-04):
-# I have been informed by users that Haiti observes DST this year like
-# last year, so the current "only" rule for 2005 might be changed to a
-# "max" rule or to last until 2006. (Who knows if they will observe DST
-# next year or if they will extend their DST like US/Canada next year).
-#
-# I have found this article about it (in French):
-# http://www.haitipressnetwork.com/news.cfm?articleID=7612
-#
-# The reason seems to be an energy crisis.
-
 
 # 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 & Pottenger say AT is 2:00, but IATA SSIM (1991/1997) says 1:00s.
-# Go with IATA.
+# 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
-Rule	Haiti	2005	max	-	Apr	Sun>=1	0:00	1:00	D
-Rule	Haiti	2005	max	-	Oct	lastSun	0:00	0	S
+Rule	Haiti	2005	only	-	Apr	Sun>=1	0:00	1:00	D
+Rule	Haiti	2005	only	-	Oct	lastSun	0:00	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 & Pottenger say 1921 Jan 1; go with Whitman's more precise Apr 1.
-
-# From Paul Eggert (2006-05-05):
-# worldtimezone.com reports a 2006-05-02 Spanish-language AP article
-# saying Honduras will start using DST midnight Saturday, effective 4
-# months until September.  La Tribuna reported today
-# <http://www.latribuna.hn/99299.html> that Manuel Zelaya, the president
-# of Honduras, refused to back down on this.
-
-# From Jesper Norgaard Welen (2006-08-08):
-# It seems that Honduras has returned from DST to standard time this Monday at
-# 00:00 hours (prolonging Sunday to 25 hours duration).
-# http://www.worldtimezone.com/dst_news/dst_news_honduras04.html
-
-# From Paul Eggert (2006-08-08):
-# Also see Diario El Heraldo, The country returns to standard time (2006-08-08)
-# <http://www.elheraldo.hn/nota.php?nid=54941&sec=12>.
-# It mentions executive decree 18-2006.
-
-# From Steffen Thorsen (2006-08-17):
-# Honduras will observe DST from 2007 to 2009, exact dates are not
-# published, I have located this authoritative source:
-# http://www.presidencia.gob.hn/noticia.aspx?nId=47
-
-# Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-Rule	Hond	1987	1988	-	May	Sun>=1	0:00	1:00	D
-Rule	Hond	1987	1988	-	Sep	lastSun	0:00	0	S
-Rule	Hond	2006	2009	-	May	Sun>=1	0:00	1:00	D
-Rule	Hond	2006	2009	-	Aug	Mon>=1	0:00	0	S
+# 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	Hond	C%sT
+			-6:00	Salv	C%sT
 #
 # Great Swan I ceded by US to Honduras in 1972
 
@@ -2321,7 +2115,7 @@ Zone America/Tegucigalpa -5:48:52 -	LMT	1921 Apr
 # From U. S. Naval Observatory (1989-01-19):
 # JAMAICA             5 H  BEHIND UTC
 
-# From Shanks & Pottenger:
+# 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
@@ -2338,16 +2132,18 @@ Zone America/Martinique	-4:04:20 -      LMT	1890		# Fort-de-France
 			-4:00	-	AST
 
 # Montserrat
-# From Paul Eggert (2006-03-22):
-# In 1995 volcanic eruptions forced evacuation of Plymouth, the capital.
-# world.gazetteer.com says Cork Hill is the most populous location now.
+# 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   # Cork Hill
+Zone America/Montserrat	-4:08:52 -	LMT	1911 Jul 1 0:01   # Olveston
 			-4:00	-	AST
 
 # Nicaragua
 #
-# This uses Shanks & Pottenger for times before 2005.
+# 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.
 #
 # From Steffen Thorsen (2005-04-12):
 # I've got reports from 8 different people that Nicaragua just started
@@ -2361,7 +2157,8 @@ Zone America/Montserrat	-4:08:52 -	LMT	1911 Jul 1 0:01   # Cork Hill
 #
 # From Paul Eggert (2005-05-01):
 # The decree doesn't say anything about daylight saving, but for now let's
-# assume that it is daylight saving....
+# assume that it is daylight saving and that they'll switch back on the
+# 3rd Sunday in September.
 #
 # From Gwillim Law (2005-04-21):
 # The Associated Press story on the time change, which can be found at
@@ -2379,35 +2176,20 @@ Zone America/Montserrat	-4:08:52 -	LMT	1911 Jul 1 0:01   # Cork Hill
 # http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm
 # (2005-09-26)
 #
-# From Jesper Norgaard Welen (2006-05-05):
-# http://www.elnuevodiario.com.ni/2006/05/01/nacionales/18410
-# (my informal translation)
-# By order of the president of the republic, Enrique Bolanos, Nicaragua
-# advanced by sixty minutes their official time, yesterday at 2 in the
-# morning, and will stay that way until 30.th. of september.
-#
-# From Jesper Norgaard Welen (2006-09-30):
-# http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2006/D-063-2006P-PRN-Cambio-Hora.pdf
-# My informal translation runs:
-# The natural sun time is restored in all the national territory, in that the
-# time is returned one hour at 01:00 am of October 1 of 2006.
-#
 # 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
 Rule	Nic	2005	only	-	Apr	10	0:00	1:00	D
-Rule	Nic	2005	only	-	Oct	Sun>=1	0:00	0	S
-Rule	Nic	2006	only	-	Apr	30	2:00	1:00	D
-Rule	Nic	2006	only	-	Oct	Sun>=1	1:00	0	S
+Rule	Nic	2005	only	-	Oct	 2	0:00	0	S
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	America/Managua	-5:45:08 -	LMT	1890
 			-5:45:12 -	MMT	1934 Jun 23 # Managua Mean Time?
 			-6:00	-	CST	1973 May
 			-5:00	-	EST	1975 Feb 16
-			-6:00	Nic	C%sT	1992 Jan  1 4:00
-			-5:00	-	EST	1992 Sep 24
-			-6:00	-	CST	1993
-			-5:00	-	EST	1997
+			-6:00	Nic	C%sT	1993 Jan 1 4:00
+			-5:00	-	EST	1998 Dec
 			-6:00	Nic	C%sT
 
 # Panama
@@ -2421,7 +2203,7 @@ Zone	America/Panama	-5:18:08 -	LMT	1890
 # 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	US	A%sT	1946
+			-4:00	1:00	AWT	1945 Sep 30  2:00
 			-4:00	-	AST
 
 # St Kitts-Nevis
@@ -2450,8 +2232,8 @@ Zone America/St_Vincent	-4:04:56 -	LMT	1890		# Kingstown
 			-4:00	-	AST
 
 # Turks and Caicos
-# From Paul Eggert (2006-03-22):
-# Shanks & Pottenger say they use US DST rules, but IATA SSIM (1991/1998)
+# 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