--- old/usr/src/cmd/zic/northamerica	Mon Mar 16 23:26:44 2015
+++ new/usr/src/cmd/zic/northamerica	Mon Mar 16 23:26:44 2015
@@ -124,7 +124,7 @@
 Rule	US	1918	1919	-	Oct	lastSun	2:00	0	S
 Rule	US	1942	only	-	Feb	9	2:00	1:00	W # War
 Rule	US	1945	only	-	Aug	14	23:00u	1:00	P # Peace
-Rule	US	1945	only	-	Sep	30	2:00	0	S
+Rule	US	1945	only	-	Sep	lastSun	2:00	0	S
 Rule	US	1967	2006	-	Oct	lastSun	2:00	0	S
 Rule	US	1967	1973	-	Apr	lastSun	2:00	1:00	D
 Rule	US	1974	only	-	Jan	6	2:00	1:00	D
@@ -277,6 +277,12 @@
 # time zone, but we do go by the Eastern time zone because so many people work
 # in Columbus."
 
+# From Paul Eggert (2014-09-06):
+# Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208
+# says that New York City Hall time was 3 minutes 58.4 seconds fast of
+# Eastern time (i.e., -4:56:01.6) just before the 1883 switch.  Round to the
+# nearest second.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER
 Rule	NYC	1920	only	-	Mar	lastSun	2:00	1:00	D
 Rule	NYC	1920	only	-	Oct	lastSun	2:00	0	S
@@ -985,20 +991,20 @@
 ################################################################################
 
 
-# From Paul Eggert (2006-03-22):
-# A good source for time zone historical data outside the U.S. is
+# From Paul Eggert (2014-10-31):
+#
+# Unless otherwise specified, the source for data through 1990 is:
 # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition),
 # San Diego: ACS Publications, Inc. (2003).
+# Unfortunately this book contains many errors and cites no sources.
 #
 # Gwillim Law writes that a good source
 # for recent time zone data is the International Air Transport
 # Association's Standard Schedules Information Manual (IATA SSIM),
 # published semiannually.  Law sent in several helpful summaries
-# of the IATA's data after 1990.
+# of the IATA's data after 1990.  Except where otherwise noted,
+# IATA SSIM is the source for entries after 1990.
 #
-# Except where otherwise noted, Shanks & Pottenger is the source for
-# entries through 1990, and IATA SSIM is the source for entries afterwards.
-#
 # Other sources occasionally used include:
 #
 #	Edward W. Whitman, World Time Differences,
@@ -1095,17 +1101,16 @@
 # An amendment to the Interpretation Act was registered on February 19/2007....
 # http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf
 
-# From Paul Eggert (2006-04-25):
+# From Paul Eggert (2014-10-18):
 # H. David Matthews and Mary Vincent's map
 # "It's about TIME", _Canadian Geographic_ (September-October 1998)
-# http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
+# http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp
 # contains detailed boundaries for regions observing nonstandard
 # time and daylight saving time arrangements in Canada circa 1998.
 #
-# INMS, the Institute for National Measurement Standards in Ottawa, has
-# information about standard and daylight saving time zones in Canada.
-# http://inms-ienm.nrc-cnrc.gc.ca/en/time_services/daylight_saving_e.php
-# (updated periodically).
+# National Research Council Canada maintains info about time zones and DST.
+# http://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html
+# http://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5
 # Its unofficial information is often taken from Matthews and Vincent.
 
 # From Paul Eggert (2006-06-27):
@@ -1970,10 +1975,7 @@
 # [Also see <http://www.nunatsiaq.com/nunavut/nvt10309_06.html> (2001-03-09).]
 
 # From Gwillim Law (2005-05-21):
-# According to maps at
-# http://inms-ienm.nrc-cnrc.gc.ca/images/time_services/TZ01SWE.jpg
-# http://inms-ienm.nrc-cnrc.gc.ca/images/time_services/TZ01SSE.jpg
-# (both dated 2003), and
+# According to ...
 # http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp
 # (from a 1998 Canadian Geographic article), the de facto and de jure time
 # for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year
@@ -1982,9 +1984,11 @@
 # predates the creation of Nunavut, it probably goes back many years....
 # The Inuktitut name of Coral Harbour is Sallit, but it's rarely used.
 #
-# From Paul Eggert (2005-07-26):
+# From Paul Eggert (2014-10-17):
 # For lack of better information, assume that Southampton Island observed
-# daylight saving only during wartime.
+# daylight saving only during wartime.  Gwillim Law's email also
+# mentioned maps now maintained by National Research Council Canada;
+# see above for an up-to-date link.
 
 # From Chris Walton (2007-03-01):
 # ... the community of Resolute (located on Cornwallis Island in
@@ -2120,11 +2124,11 @@
 
 # Mexico
 
-# From Paul Eggert (2001-03-05):
+# From Paul Eggert (2014-12-07):
 # The Investigation and Analysis Service of the
 # Mexican Library of Congress (MLoC) has published a
 # history of Mexican local time (in Spanish)
-# http://www.cddhcu.gob.mx/bibliot/publica/inveyana/polisoc/horver/
+# http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm
 #
 # Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC.
 # (In all cases we go with the MLoC.)
@@ -2293,6 +2297,24 @@
 # efecto desde las dos horas del segundo domingo de marzo y concluirá a
 # las dos horas del primer domingo de noviembre.
 
+# From Steffen Thorsen (2014-12-08), translated by Gwillim Law:
+# The Mexican state of Quintana Roo will likely change to EST in 2015.
+#
+# http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo
+# "With this change, the time conflict that has existed between the municipios
+# of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an
+# end. The latter declared itself in rebellion 15 years ago when a time change
+# was initiated in Mexico, and since then it has refused to change its time
+# zone along with the rest of the country."
+#
+# From Steffen Thorsen (2015-01-14), translated by Gwillim Law:
+# http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html
+# "...the new time zone will come into effect at two o'clock on the first Sunday
+# of February, when we will have to advance the clock one hour from its current
+# time..."
+#
+# Also, the new zone will not use DST.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Mexico	1939	only	-	Feb	5	0:00	1:00	D
 Rule	Mexico	1939	only	-	Jun	25	0:00	0	S
@@ -2313,7 +2335,8 @@
 Zone America/Cancun	-5:47:04 -	LMT	1922 Jan  1  0:12:56
 			-6:00	-	CST	1981 Dec 23
 			-5:00	Mexico	E%sT	1998 Aug  2  2:00
-			-6:00	Mexico	C%sT
+			-6:00	Mexico	C%sT	2015 Feb  1  2:00
+			-5:00	-	EST
 # Campeche, Yucatán; represented by Mérida
 Zone America/Merida	-5:58:28 -	LMT	1922 Jan  1  0:01:32
 			-6:00	-	CST	1981 Dec 23
@@ -2985,10 +3008,21 @@
 # Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an
 # unspecified official document, and says "This time is used throughout the
 # island".  Go with Milne.  Round to the nearest second as required by zic.
+#
+# Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but
+# Lance Neita writes that Prime Minister Michael Manley decreed it January 5.
+# Assume Neita meant Jan 6 02:00, the same as the US.  Neita also writes that
+# Manley's supporters associated this act with Manley's nickname "Joshua"
+# (recall that in the Bible the sun stood still at Joshua's request),
+# and with the Rod of Correction which Manley said he had received from
+# Haile Selassie, Emperor of Ethiopia.  See:
+# Neita L. The politician in all of us. Jamaica Observer 2014-09-20
+# http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647
+#
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	America/Jamaica	-5:07:11 -	LMT	1890        # Kingston
 			-5:07:11 -	KMT	1912 Feb    # Kingston Mean Time
-			-5:00	-	EST	1974 Apr 28  2:00
+			-5:00	-	EST	1974
 			-5:00	US	E%sT	1984
 			-5:00	-	EST
 
@@ -3116,13 +3150,17 @@
 # From Paul Eggert (2014-08-19):
 # The 2014-08-13 Cabinet meeting decided to stay on UTC-4 year-round.  See:
 # http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm
-# Model this as a switch from EST/EDT to AST on 2014-11-02 at 02:00.
+# Model this as a switch from EST/EDT to AST ...
+# From Chris Walton (2014-11-04):
+# ... the TCI government appears to have delayed the switch to
+# "permanent daylight saving time" by one year....
+# http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm
 #
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone America/Grand_Turk	-4:44:32 -	LMT	1890
 			-5:07:11 -	KMT	1912 Feb # Kingston Mean Time
 			-5:00	-	EST	1979
-			-5:00	US	E%sT	2014 Nov  2  2:00
+			-5:00	US	E%sT	2015 Nov Sun>=1 2:00
 			-4:00	-	AST
 
 # British Virgin Is
