[tz] Reason for 24:00

Paul Eggert eggert at cs.ucla.edu
Sat May 4 00:32:40 UTC 2019

On 5/2/19 7:43 AM, Marketa Calabkova wrote:
> I am just wondering why there is 24:00 in the AT column for some
> countries (including Iran, Amman and Santiago) while there is 0:00
> elsewhere.

Sometimes the legislation or other source says midnight at the end of
the day, sometimes it says midnight at the start of the day. Using 0:00
or 24:00 lets us follow the source as closely as possible. In a few
cases (e.g., "24:00 the last Saturday in March") it's not that easy to
switch between 0 and 24, so we might use 24:00 even if the original
source uses a more circumlocutory form with 00:00.

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