Nothing more corporate / enterprise than deciding the year starts at any point other than January 1st :) (yeah I know all about the fiscal year, which I also find hilarious)
Some of them don't even start on a month boundary, or even on the same day every year. Cisco, for instance, has a fiscal year based on a retail calendar[0]; their fiscal year ends on the last full week in July.
Well yes for a strictly non-consumer company, since their revenues don't depend on Superbowl, Valentine's Day, Easter, Memorial Day, Fourth of July, Amazon Prime Day, Labor Day, Thanksgiving/Cyber Monday, Christmas. They probably depend more on Fed rate cuts/rises affecting corporate infrastructure budget.
("Honey I got you that Cisco 4500 you always wanted...")
Whereas for anything consumer e-commerce, you'd want a calendar with variable/sliding dates (e.g. SuperBowl) but that at least keeps the above events in the same quarter YoY, consistently.
not to be THAT NERD but in the UK at least, the financial year (April 6th - April 5th) was aligned with the start of the new year which was March 25th.
The old financial year started on 25th March, which was also new year's day (and also the point that the year incremented, so if you were knocking around on March 24th 1300 the next day would be March 25th 1301.
But when everyone changed to the Gregorian Calendar - which added 11 days to the calendar to make up for some sloppy Papal mathematicians who didn't believe in things like astronomy or leap years - the tax year had to be shifted to be April 6th, because while everyone else was happy to work around things, the tax office was NOT going to have a tax year that was 11 days shorter because that would have meant less money.
So basically, when the calendar changed happened, new year was set as 1st January (yawn, stupid time to have new year!) at which point the year count incremented up by one year, and the tax year stayed (and still stays) as April 6th, which was really March 25th but with some days tacked on.
ISO 8601 allowing week-based year numbering is even more insane. E.g. In 2007-12-31 (in RFC 3339 format) is allowed to be notated as 2008-W01-1 in ISO 8601. RFC 3339 is superior, partly because it prevents this bullshit.
ISO week numbering is actually sort of neat, because instead of leap days it has entire leap weeks since the 400-year Gregorian cycle has a whole number of weeks in it, but for some reason they decided that a week's year is the Gregorian year in which the Thursday of that week occurs.
