[tz] Comments and mapping of tz zones to the real world

Kevin Kenny kkenny2 at nycap.rr.com
Sun May 6 06:49:48 UTC 2012

On 05/06/2012 02:03 AM, Tobias Conradi wrote:

> Can you tell a way of how a user determines the correct zone for a
> random location in Indiana, selecting between
> America/Indiana/Indianapolis
> America/Indiana/Vincennes
> America/Indiana/Winamac
> America/Indiana/Marengo
> America/Indiana/Petersburg
> America/Indiana/Vevay
> America/Kentucky/Louisville
> America/New York
> without reading the comments?

Fortunately, nearly everyone in Indiana is aware of the bizarre
timezone patchwork.

The simple rule, "if you're in Eastern time with DST, use New_York,
if you're in Eastern time without DST, use Indianapolis; if you're
in Central time, use Chicago" is correct for 99% of them, because
the breakaway counties are farmland with few inhabitants.  Out
in the hinterland, it becomes "if you are in one of the half-dozen
counties that have their own zones (named like the counties), use

If you were to pick a random location on a map in Indiana and ask
what time is observed there, I'd be hard pressed to answer.  But
in that particular case, better mapping might not even help; a great
many inhabitants and businesses set their clocks to the large cities
of Chicago or Indianapolis rather than whatever time their county
legislatures have decided to observe that year.

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