Mataveri only airport?

[Paul Eggert]

Jesper Norgaard Welen <jnorgard at prodigy.net.mx> writes:

> Luckily the timezone
> involved is called "Pacific/Easter" so there is no problem with that. It
> seems that only the explicit use of Mataveri Mean Time MMT and the
> commentary in the southamerica file is affected. Perhaps the latitude and
> longitude coordinates in zone.tab.

The existing offset of -7;17:28 is not that of Mataveri, it's taken
directly from Shanks (who perhaps just threw a dart at the Easter
Island map).  So clearly the "MMT" is wrong, and I'd say we should
replace it with "EMT" or maybe "EIMT".

I'm skeptical of the pre-1980 time stamps for Pacific/Easter, but we
have no other source, and in the meantime we might as well stick with
what Shanks gives us.

Something like the following patch, perhaps?  I'm not yet proposing
it, just asking for another pair of eyes to check it.

--- zone.tab	2006/11/27 13:53:52	2006.16
+++ zone.tab	2006/12/27 21:44:14
@@ -134,7 +134,7 @@ CH	+4723+00832	Europe/Zurich
 CI	+0519-00402	Africa/Abidjan
 CK	-2114-15946	Pacific/Rarotonga
 CL	-3327-07040	America/Santiago	most locations
-CL	-2710-10927	Pacific/Easter	Easter Island & Sala y Gomez
+CL	-2709-10926	Pacific/Easter	Easter Island & Sala y Gomez
 CM	+0403+00942	Africa/Douala
 CN	+3114+12128	Asia/Shanghai	east China - Beijing, Guangdong, Shanghai, etc.
 CN	+4545+12641	Asia/Harbin	Heilongjiang (except Mohe), Jilin
--- southamerica	2006/11/06 14:17:39	2006.15
+++ southamerica	2006/12/27 21:39:14
@@ -714,8 +714,13 @@ Zone America/Rio_Branco	-4:31:12 -	LMT	1
 # (they should have been 1990-09-15 and 1990-09-16 respectively), but
 # anyhow it clears up some doubts too.
 
-# The following data are from <http://www.horaoficial.cl/horaof.htm>
-# (2006-09-20), transcribed by Jesper Norgaard Welen.
+# From Paul Eggert (2006-12-27):
+# The following data for Chile and America/Santiago are from
+# <http://www.horaoficial.cl/horaof.htm> (2006-09-20), transcribed by
+# Jesper Norgaard Welen.  The data for Pacific/Easter are from Shanks
+# & Pottenger, except with DST transitions after 1932 cloned from
+# America/Santiago.  Most likely the pre-1980 Pacific/Easter data are
+# wrong, but we have no other source.
 
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
 Rule	Chile	1927	1932	-	Sep	 1	0:00	1:00	S
@@ -759,9 +764,9 @@ Zone America/Santiago	-4:42:46 -	LMT	189
 			-4:42:46 -	SMT	1927 Sep  1 # Santiago Mean Time
 			-5:00	Chile	CL%sT	1947 May 22 # Chile Time
 			-4:00	Chile	CL%sT
-Zone Pacific/Easter	-7:17:28 -	LMT	1890	    # Mataveri
-			-7:17:28 -	MMT	1932 Sep    # Mataveri Mean Time
-			-7:00	Chile	EAS%sT	1982 Jan 18 21:00 # Easter I Time
+Zone Pacific/Easter	-7:17:28 -	LMT	1890
+			-7:17:28 -	EMT	1932 Sep    # Easter Mean Time
+			-7:00	Chile	EAS%sT	1982 Mar 13 21:00 # Easter I Time
 			-6:00	Chile	EAS%sT
 #
 # Sala y Gomez Island is like Pacific/Easter.