This comes from tzdata2009s, southamerica file
The rules are
#
Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
Rule Brazil 2008 max - Oct Sun>=15 0:00 1:00 S
Rule Brazil 2008 2011 - Feb Sun>=15 0:00 0 -
Rule Brazil 2012 only - Feb Sun>=22 0:00 0 -
Rule Brazil 2013 2014 - Feb Sun>=15 0:00 0 -
The
Timezone
#
# east Amazonas
(AM): Boca do Acre, Jutai, Manaus, Floriano Peixoto
# The great
circle line from Tabatinga to Porto Acre divides
# east from
west Amazonas.
Zone America/Manaus -4:00:04
- LMT 1914
-4:00 Brazil AM%sT 1988 Sep 12
-4:00 - AMT 1993 Sep 28
-4:00 Brazil AM%sT 1994 Sep 22
-4:00 - AMT
From what I understand from the above,
America/Manaus does not observe DST ever
since Sep 22, 1994.
However, looking at the Microsoft Timezone
definition [Dec 2009 update]
for (GMT -4:00) Manaus [Central Brazilian
Standard Time]
the timezone observe DST from 3rd Saturday of
October 23:59:59 to 3rd Saturday of
February, 23:59:59.
Also, another non-official site seems to imply the
same:
[http://www.icfsi2007.com/city_more.php will
show
Time
Manaus Time Zone is 1 hour
less than Brasilia, Sao Paulo or Rio de Janeiro Time Zone (GMT - 03:00),
four hours behind of Greenwich Mean Time (GMT),
except during the period between late October and the end
of February,
when daylight saving time is in force (GMT -
05:00 hours).
]
So either
a) I do not interpret the timezone rules properly
for America/Manaus, and there is a
DST being observed there.
If so, please let me know how I should
read the above rules/timezone information.
b) Microsoft timezone is incorrect
c) Olson data is incorrect
d) The Microsoft timezone [(GMT -4:00) Manaus -
Central Brazilian Standard Time] does not
correspond to the
Olson's America/Manaus timezone
Your opinion would be
appreciated
Thanks
-Alain Petit