proposed patch for Guatemala, Nicaragua, Indiana, Nova Scotia, etc.

Paul Eggert eggert at CS.UCLA.EDU
Thu Apr 27 07:57:33 UTC 2006


Since the Guatemala and Nicaragua changes are relatively urgent, here
are the proposed tz patches that I've been accumulating recently.
Thanks again to everyone who's contributed.

Changes to time stamps that take effect this weekend:

* Guatemala has DST this year from 04-30 00:00 to 10-01 00:00.
  (Thanks to Oscar van Vlijmen and Gwillim Law for this info.)

* Nicaragua has DST this year from 04-30 02:00 to sometime around September
  1, we think; for now, guess 09-03 02:00.  (Thanks to worldtimezone.com
  and Jesper Norgaard Welen for this info.)

Changes to historical time stamps:

* Nicaragua's early 1990s experiment was in 1992, not 1993, fixing a
  typo in my earlier reading of Shanks.  Also, the experiment changed
  standard time temporarily instead of instituting DST.  The late
  1990s change was in 1997, not 1998.  (This is all taken from the
  latest edition of Shanks & Pottenger, for which thanks.)

Changes to zone.tab and commentary only:

* Martin and Pulaski Counties, Indiana, have decided not to rebel against
  the federal decision after all.

Changes to commentary only.

* Nova Scotia and Northwest Territories announced they will follow the
  US lead next year too.  (Thanks to Chris Walton for this.)

* The Philippines are considering adopting DST this June, and may have
  used DST for a month or so in 1990.  (Thanks to Jesper Norgaard Welen
  for the info about 1990.)

* Common usage for Sri Lanka's local time might not be "IST" these
  days.  (Thanks to Nimal Ratnayake and K Sethu for this info; they
  are looking into what common practice is after things settle down
  after the recent UTC offset change.)

* Wisconsin state law specifies 01:00 as the legal DST switchover
  time, even though everybody actually switches at 02:00; this leads
  to tickets being given to bar owners.  (Thanks to Larry M. Smith for
  this info.)

* The wording for the Mandan 2003-10-26 switch was unclear.
  (Thanks to Jesper Norgaard Welen for this.)

===================================================================
RCS file: RCS/asia,v
retrieving revision 2006.4
retrieving revision 2006.4.0.1
diff -pu -r2006.4 -r2006.4.0.1
--- asia	2006/04/17 18:30:44	2006.4
+++ asia	2006/04/27 06:43:00	2006.4.0.1
@@ -1467,6 +1467,20 @@ Zone	Asia/Gaza	2:17:52	-	LMT	1900 Oct
 # be immediately followed by 1845-01-01.  Robert H. van Gent has a
 # transcript of the decree in <http://www.phys.uu.nl/~vgent/idl/idl.htm>.
 # The rest of the data are from Shanks & Pottenger.
+
+# From Paul Eggert (2006-04-25):
+# Tomorrow's Manila Standard reports that the Philippines Department of
+# Trade and Industry is considering adopting DST this June when the
+# rainy season begins.  See
+# <http://www.manilastandardtoday.com/?page=politics02_april26_2006>.
+# For now, we'll ignore this, since it's not definite and we lack details.
+#
+# From Jesper Norgaard Welen (2006-04-26):
+# ... claims that Philippines had DST last time in 1990:
+# http://story.philippinetimes.com/p.x/ct/9/id/145be20cc6b121c0/cid/3e5bbccc730d258c/
+# [a story dated 2006-04-25 by Cris Larano of Dow Jones Newswires,
+# but no details]
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Phil	1936	only	-	Nov	1	0:00	1:00	S
 Rule	Phil	1937	only	-	Feb	1	0:00	0	-
@@ -1531,6 +1545,44 @@ Zone	Asia/Singapore	6:55:25 -	LMT	1901 J
 # 0030 hrs on April 15, 2006 (midnight of April 14, 2006 +30 minutes)
 # at present, become 2400 hours of April 14, 2006 (midnight of April 14, 2006).
 
+# From Peter Apps and Ranga Sirila of Reuters (2006-04-12) in:
+# <http://today.reuters.co.uk/news/newsArticle.aspx?type=scienceNews&storyID=2006-04-12T172228Z_01_COL295762_RTRIDST_0_SCIENCE-SRILANKA-TIME-DC.XML>
+# [The Tamil Tigers] never accepted the original 1996 time change and simply
+# kept their clocks set five and a half hours ahead of Greenwich Mean
+# Time (GMT), in line with neighbor India.
+# From Paul Eggert (2006-04-18):
+# People who live in regions under Tamil control can use TZ='Asia/Calcutta',
+# as that zone has agreed with the Tamil areas since our cutoff date of 1970.
+
+# From K Sethu (2006-04-25):
+# I think the abbreviation LKT originated from the world of computers at
+# the time of or subsequent to the time zone changes by SL Government
+# twice in 1996 and probably SL Government or its standardization
+# agencies never declared an abbreviation as a national standard.
+#
+# I recollect before the recent change the government annoucemments
+# mentioning it as simply changing Sri Lanka Standard Time or Sri Lanka
+# Time and no mention was made about the abbreviation.
+#
+# If we look at Sri Lanka Department of Government's "Official News
+# Website of Sri Lanka" ... http://www.news.lk/ we can see that they
+# use SLT as abbreviation in time stamp at the beginning of each news
+# item....
+#
+# Within Sri Lanka I think LKT is well known among computer users and
+# adminsitrators.  In my opinion SLT may not be a good choice because the
+# nation's largest telcom / internet operator Sri Lanka Telcom is well
+# known by that abbreviation - simply as SLT (there IP domains are
+# slt.lk and sltnet.lk).
+#
+# But if indeed our government has adopted SLT as standard abbreviation
+# (that we have not known so far) then  it is better that it be used for
+# all computers.
+
+# From Paul Eggert (2006-04-25):
+# One possibility is that we wait for a bit for the dust to settle down
+# and then see what people actually say in practice.
+
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
 Zone	Asia/Colombo	5:19:24 -	LMT	1880
 			5:19:32	-	MMT	1906	# Moratuwa Mean Time
===================================================================
RCS file: RCS/northamerica,v
retrieving revision 2006.4
retrieving revision 2006.4.0.2
diff -pu -r2006.4 -r2006.4.0.2
--- northamerica	2006/04/17 18:30:44	2006.4
+++ northamerica	2006/04/27 07:36:46	2006.4.0.2
@@ -301,6 +301,13 @@ Zone America/New_York	-4:56:02 -	LMT	188
 # 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
@@ -322,7 +329,7 @@ Zone America/North_Dakota/Center -6:45:1
 			-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.
+# 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;
@@ -544,17 +551,9 @@ Zone America/Boise	-7:44:49 -	LMT	1883 N
 # - Clark, Floyd, and Harrison counties have been like
 #   America/Kentucky/Louisville.
 #
-# - Daviess, Dubois, Knox, and Perry counties
+# - Daviess, Dubois, Knox, Martin, Perry, and Pulaski counties
 #   have been like America/Indiana/Vincennes.
 #
-# - Officially, Martin and Pulaski counties have also been like
-#   America/Indiana/Vincennes, but an AP article on Pulaski county
-#   <http://www.indystar.com/apps/pbcs.dll/article?AID=/20060207/NEWS01/602070408/1006>
-#   (2006-02-07) and an InsideINdianaBusiness.com report on Martin county
-#   <http://www.insideindianabusiness.com/newsitem.asp?ID=17202> (2006-03-15)
-#   say that the county commissioners have voted to stay on eastern time in
-#   2006, which means they are actually like America/Indiana/Indianopolis.
-#
 # - Crawford, Pike, Starke, and Switzerland counties have their own time zone
 #   histories as noted below.
 #
@@ -619,7 +618,7 @@ Zone America/Indiana/Marengo -5:45:23 -	
 			-5:00	-	EST	2006
 			-5:00	US	E%sT
 #
-# Daviess, Dubois, Knox, and Perry Counties, Indiana,
+# Daviess, Dubois, Knox, Martin, Perry, and Pulaski Counties, Indiana,
 # switched from eastern to central time in April 2006.
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER
 Rule Vincennes	1946	only	-	Apr	lastSun	2:00	1:00	D
@@ -901,7 +900,7 @@ Zone America/Menominee	-5:50:27 -	LMT	18
 # U.S. and the rest of Canada....
 # http://www2.news.gov.bc.ca/news_releases_2005-2009/2006AG0014-000330.htm
 
-# From Paul Eggert (2006-04-09):
+# From Paul Eggert (2006-04-25):
 # 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)
@@ -915,7 +914,7 @@ Zone America/Menominee	-5:50:27 -	LMT	18
 # Its unofficial information is often taken from Matthews and Vincent.
 #
 # CBC News reported that Ontario and Manitoba have announced plans to
-# follow the US change, and that Nova Scotia is considering it; see
+# follow the US change; 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
@@ -1016,6 +1015,11 @@ Zone America/Goose_Bay	-4:01:40 -	LMT	18
 # in Canada to observe DST in 1971 but not 1970; for now we'll assume
 # this is a typo.
 
+# 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
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Halifax	1916	only	-	Apr	 1	0:00	1:00	D
 Rule	Halifax	1916	only	-	Oct	 1	0:00	0	S
@@ -1593,6 +1597,10 @@ Zone America/Dawson_Creek -8:00:56 -	LMT
 # From Paul Eggert (2005-07-26):
 # For lack of better information, assume that Southampton Island observed
 # daylight saving only during wartime.
+#
+# From Chris Walton (2006-04-25):
+# Daylight saving time will be extended by four weeks starting in 2007....
+# http://www.cbc.ca/north/story/nor-nwt-time-change.html
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	NT_YK	1918	only	-	Apr	14	2:00	1:00	D
@@ -2097,6 +2105,14 @@ Zone America/Guadeloupe	-4:06:08 -	LMT	1
 			-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).
 # 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
@@ -2104,6 +2120,8 @@ 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
@@ -2198,9 +2216,7 @@ Zone America/Montserrat	-4:08:52 -	LMT	1
 
 # Nicaragua
 #
-# From Steffen Thorsen (1998-12-29):
-# Nicaragua seems to be back at -6:00 but I have not been able to find when
-# they changed from -5:00.
+# This uses Shanks & Pottenger for times before 2005.
 #
 # From Steffen Thorsen (2005-04-12):
 # I've got reports from 8 different people that Nicaragua just started
@@ -2214,8 +2230,7 @@ Zone America/Montserrat	-4:08:52 -	LMT	1
 #
 # 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 and that they'll switch back on the
-# 3rd Sunday in September.
+# assume that it is daylight saving....
 #
 # From Gwillim Law (2005-04-21):
 # The Associated Press story on the time change, which can be found at
@@ -2233,20 +2248,32 @@ Zone America/Montserrat	-4:08:52 -	LMT	1
 # http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm
 # (2005-09-26)
 #
+# From Jesper Norgaard Welen (2006-04-24):
+# http://www.elnuevodiario.com.ni/2006/04/26/nacionales/18036
+# It claims that DST will start 2006-04-30 at 2:00, and will last until the
+# end of august (without being more specific).
+# From Paul Eggert (2006-04-26):
+# Yesterday the president of Nicaragua announced that DST will begin
+# April 30 at 02:00.  No end date was announced.
+# http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Comunicados/2006/PRESIDENTE/250406-Que%20la%20Crisis%20originada%20por%20el%20alza%20constante%20de%20los%20precios%20internacionales.htm
+# For now, assume DST ends first Sunday in September at 02:00.
+#
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Nic	1979	1980	-	Mar	Sun>=16	0:00	1:00	D
 Rule	Nic	1979	1980	-	Jun	Mon>=23	0:00	0	S
-Rule	Nic	1992	only	-	Jan	 1	4:00	1:00	D
-Rule	Nic	1992	only	-	Sep	24	0:00	0	S
 Rule	Nic	2005	only	-	Apr	10	0:00	1:00	D
 Rule	Nic	2005	only	-	Oct	 2	0:00	0	S
+Rule	Nic	2006	only	-	Apr	30	2:00	1:00	D
+Rule	Nic	2006	only	-	Sep	Sun>=1	2:00	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	1993 Jan 1 4:00
-			-5:00	-	EST	1998 Dec
+			-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
 
 # Panama
===================================================================
RCS file: RCS/zone.tab,v
retrieving revision 2006.3
retrieving revision 2006.3.0.1
diff -pu -r2006.3 -r2006.3.0.1
--- zone.tab	2006/04/03 14:04:45	2006.3
+++ zone.tab	2006/04/27 06:43:00	2006.3.0.1
@@ -376,7 +376,7 @@ US	+382232-0862041	America/Indiana/Maren
 US	+411745-0863730	America/Indiana/Knox	Eastern Time - Indiana - Starke County
 US	+384452-0850402	America/Indiana/Vevay	Eastern Time - Indiana - Switzerland County
 US	+415100-0873900	America/Chicago	Central Time
-US	+384038-0873143	America/Indiana/Vincennes	Central Time - Indiana - Daviess, Dubois, Knox & Perry Counties
+US	+384038-0873143	America/Indiana/Vincennes	Central Time - Indiana - Daviess, Dubois, Knox, Martin, Perry & Pulaski Counties
 US	+382931-0871643	America/Indiana/Petersburg	Central Time - Indiana - Pike County
 US	+450628-0873651	America/Menominee	Central Time - Michigan - Dickinson, Gogebic, Iron & Menominee Counties
 US	+470659-1011757	America/North_Dakota/Center	Central Time - North Dakota - Oliver County



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