On Thu, 10 Apr 2008 11:45:13 -0400, Howard Schreier <hs AT dc-sug DOT org>
>On Thu, 10 Apr 2008 11:26:09 -0400, Fehd, Ronald J. (CDC/CCHIS/NCPHI)
>>zero as an Excel date is Jan 1, 1900
>I believe it's 30 Dec. 1899
well, it sounds ridiculous, but excel date is messier, to say the least.
excel has two date systems. They are called 1900 and 1904 date systems. You
can switch back and force, but the default on excel for windows is the 1900
date system and the default on excel for macs is the 1904 date system.
with 1900 date system, the day 1 is Jan 1, 1900. and this is the first date
-- meaning excel won't accept the date value of any day before Jan 1, 1900.
if you date format a zero(0), then it returns something silly like:
Saturday, January 00, 1900.
Not only that, excel, following lotus 1-2-3, considers the year 1900 as a
leap year (which in fact is not) adding a non-existing day (Feb 29, 1900) in
as date value 60.
under the 1904 date system, on the other hand, Jan 2, 1904 is the day 1.
I thought sas' date was confusing, didn' you? :-)