On Wed, 11 Jul 2007 17:50:54 +0100 Harold Fuchs wrote: > Could this be connected to the fact that Excel wrongly believes that > 1900 was a leap year? > Dates are stored as the number of dates since some "epoc" date, often > 1/1/1900. Using this we see that, using *Excel* > > 1 Jan 1900 is stored as 0 (zero days *after* 1/1/1900) > 31 Jan 1900 ........... 30 > 1 Feb 1900 ........... 31 > 28 Feb 1900 ........... 58 > > At this point things start going awry. Excel believes there is a 29 > Feb 1900 and, if it saw this date, *would* store it as 59. So we get > (*wrongly*) > > 29 Feb stored as 59 > 1 Mar as 60 > 2 Mar as 61 and so on. > > Of course, because of this phantom 29 Feb, > > 59 should be 1 Mar > 60 should be 2 Mar > 61 should be 3 Mar and so on. > > Now, OpenOffice Calc *knows* this so, when it sees a .ods (Calc) file > with a date 61 it shows it as 3 Mar but when it sees a .xls (Excel) > file with the *same* value it adjusts to show it as 2 Mar. >
Before someone jumps in and says that 1900 was a leap year i will pipe up. All years divisible by 4 are leap years * except all years divisible by 100 are not leap years * * Except all years divisible by 400 are leap years. So 1900 was not a leap year, 2000 was a one in 400 leap year and 2100 will not be a leap year. http://en.wikipedia.org/wiki/Leap_year#Gregorian_calendar -- Michael Linux: The OS people choose without $200,000,000 of persuasion. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
