Time in Falkland Islands and Moldova

Paul Eggert eggert at twinsun.com
Mon Feb 12 07:08:23 UTC 2001

> Date: Thu, 25 Jan 2001 00:10:15 -0600
> From: <jnorgard at Prodigy.Net.mx>

> I decided to check it out with some searches in Internet, but didn't
> find anything remotely authoritative, but did find some
> english-speaking persons with e-mail that were apparently living in
> Tiraspol. I sent mails to 4 persons and got 2 replies:

Thanks for checking into this.  On further investigation, the existing
Europe/Tiraspol entry (which is taken from Shanks) is most likely
incorrect.  I'll correct this in my next proposed patch.

> # Falklands...
> Rule	Falk	1985	1995	-	Sep	Sun>=9	0:00	1:00	S
> Rule	Falk	1986	max	-	Apr	Sun>=16	0:00	0	-
> Rule	Falk	1996	max	-	Sep	Sun>=8	0:00	1:00	S

> The rules "Sun>=9" that was later substituted with "Sun>=8", and
> "Sun>=16", arose my curiosity. The rule "Sun>=9" means the Sunday
> after the Second Saturday which is pretty awkward to say the least
> (but possible)

Yes.  That rule was inferred from the Shanks data before 1990 and the
IATA data through February 2000.  For example, both IATA and Shanks
give 1991-09-15, and Shanks gives 1985-09-15.  Unfortunately this data
lists only dates and times, so I don't know the actual rules.  The
Sun>=9 rule resembles the rule that we know is used in Chile, so it's
not entirely implausible, but I admit that there's a lot of guesswork

> It just so happens that 1996 was the first year in several years
> back where it would make a difference which rule to use. With the
> first rule we would get the 15.th. September, while the second rule
> we would get the 8.th. September.

Just to make things interestings, Shanks says that the 1996 transition
occurred on 15 September, but I was going with the IATA data which
gives 8 September.  This is the only date between 1990 and 2000
(inclusive) for which the two sources disagree.

> Similarly looking at the rule "Sun>=16" it means the Sunday after
> the third Saturday, which is an awkward rule and not supported by
> Windows.

Yes.  However, Shanks gives 1990-04-22, which is a counterexample to
Sun>=15.  (Perhaps they didn't use Windows much in the Falklands back
then.  :-)  Our IATA data do not go back that far.

Thanks for finding out the official Falklands rule for this year.
I'll update the tables and (for lack of better info) assume the switch
occurred at the start of this year.

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