01-06-2025, 01:48 AM
(01-05-2025, 11:51 AM)macalwen Wrote: October 4, 1582 week 4, before this date the Julian calendar was used, with a leap year every 4 years, and working backwards from this, then January 1, 1 AD was week 6, October 5 to 14, 1582 was canceled, so October 15, 1582 was week 5, and from this date onwards the Gregorian calendar was used, with a slightly different calculation of leap years. To take all of this into account, it can only be calculated separately.I put a +2 on your initial post for addressing the calendar change up. It made me decide to stop my routine from going back prior to 1583. I use it for appointments, so unless I make a time machine... Which if I ever do you'd think I know about it by now, going back in times past the first day of use was not something I was concerned about. At least now it can't be misused in that regard,
Pete