From d582a6e3b650d3f66ac43968696ee94b53166f1a Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 2 Mar 2017 01:30:19 -0800 Subject: [PROPOSED] Fix Liberia 1972 transition and pre-1972 abbr * NEWS: Document this. * africa (Africa/Monrovia): The 1972 transition was on January 7, not May 1. (Shanks was wrong again! and Howse was right.) Use MMT for pre-1972 abbreviation. --- NEWS | 10 ++++++++++ africa | 25 ++++++++++++++++--------- 2 files changed, 26 insertions(+), 9 deletions(-) diff --git a/NEWS b/NEWS index 306685a..b3917d0 100644 --- a/NEWS +++ b/NEWS @@ -1,5 +1,15 @@ News for the tz database +Unreleased, experimental changes + + Changes to past time stamps + + Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01. + + Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430" + is one byte over the POSIX limit. (Problem reported by Derick Rethans.) + + Release 2017a - 2017-02-28 00:05:36 -0800 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia diff --git a/africa b/africa index e617396..dcc20b9 100644 --- a/africa +++ b/africa @@ -420,18 +420,25 @@ Link Africa/Nairobi Indian/Mayotte # See Africa/Johannesburg. # Liberia -# From Paul Eggert (2006-03-22): -# In 1972 Liberia was the last country to switch -# from a UTC offset that was not a multiple of 15 or 20 minutes. -# Howse reports that it was in honor of their president's birthday. -# Shank & Pottenger report the date as May 1, whereas Howse reports Jan; -# go with Shanks & Pottenger. -# For Liberia before 1972, Shanks & Pottenger report -0:44, whereas Howse and -# Whitman each report -0:44:30; go with the more precise figure. +# +# From Paul Eggert (2017-03-02): +# +# The Nautical Almanac for the Year 1970, p 264, is the source for -0:44:30. +# +# In 1972 Liberia was the last country to switch from a UTC offset +# that was not a multiple of 15 or 20 minutes. The 1972 change was on +# 1972-01-07, according to an entry dated 1972-01-04 on p 330 of: +# Presidential Papers: First year of the administration of +# President William R. Tolbert, Jr., July 23, 1971-July 31, 1972. +# Monrovia: Executive Mansion. +# +# Use the abbreviation "MMT" before 1972, as the more-accurate numeric +# abbreviation "-004430" would be one byte over the POSIX limit. +# # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Africa/Monrovia -0:43:08 - LMT 1882 -0:43:08 - MMT 1919 Mar # Monrovia Mean Time - -0:44:30 - -004430 1972 May + -0:44:30 - MMT 1972 Jan 7 # approximately MMT 0:00 - GMT ############################################################################### -- 2.7.4