[outofsalt]

Approximately 365.25 days in a year, hence leap years.
The next one is 2024. Even that is not exactly accurate.

[Nateman]

That huge earthquake in the Pacific that killed so many recently with a tsunami actually changed the length of a day ever so slightly.

[Deo volente]

Approximately 365.25 days in a year, hence leap years. The next one is 2024. Even that is not exactly accurate.

That's right. It has to be adjusted by making every century year a leap year only if it's divisible by 400 without a remainder. So 2000 was a leap year, but 2100, 2200, and 2300 will not be.