interpretation of Rule

[Garrett Wollman]

<<On Fri, 4 Feb 2011 14:54:21 -0500, <mxtaylor at ups.com> said:

> Sorry I am also new to this and am trying to understand how the rule below is applied:
> # Ghana
> # Rule    NAME      FROM      TO        TYPE      IN        ON        AT        SAVE      LETTER/S
> Rule      Ghana     1936      1942      -         Sep        1        0:00      0:20      GHST
> Rule      Ghana     1936      1942      -         Dec       31        0:00      0         GMT

> I read it as "Ghana" rules were only in effect from 1936 to 1942.

This is a common confusion.  The Rule statements generate transitions;
in this case, every year between 1936 and 1942, two transitions are
generated, one from GMT to GHST (save 20 minutes), and one from GHST
to GMT.  Since no transitions happen after December 31, 1942, Ghana
remains on GMT.

-GAWollman