[Telepathic Intruder]

What it boils down to is that there is not an exactly even number of earth spins for every year, and there's no reason there should be. So some compensation is needed. The leap year system goes like this:

It's a leap year if the year is divisible by 4, unless it's also divisible by 100 in which case it's not, unless it's also divisible by 400 in which case it is.

This results in a year which is 365.2422 days long. Very close but not exact, although we shouldn't have to worry about it for several thousand years.

[Celtic Conservative]

The Atomic clocks have been in the habit of introducing “leap seconds” in order that things stay evened up.

CC