"Hmm, oh, this form wants a date. Let me put in today's date..." Well, maybe not.

Lots of people might use 2000 as a fake date, the way I usually use 1900 (except on websites that don't believe people over the age of 70-80 still exist).

Maybe it's a Y2K error.

Maybe there are 1,000,000 journals devoted to people's cats, satellites, and babies.

Maybe their software is broken, and doing subtraction wrong.