This info comes from “infoplease.com.” Some of this may be review from elementary school, but I found it interesting, nonetheless. If you don’t care to know the nitty-gritty details of leap year, there’s no need to keep reading!
Why do we need leap year? ~ The Gregorian calendar, which now serves as the standard calendar for civil use throughout the world, has both common years and leap years. A common year has 365 days and a leap year 366 days, with the extra, or intercalary, day designated as February 29. A leap year occurs every four years to help synchronize the calendar year with the solar year, or the length of time it takes the earth to complete its orbit about the sun, which is about 365¼ days.
The length of the solar year, however, is slightly less than 365¼ days—by about 11 minutes. To compensate for this discrepancy, the leap year is omitted three times every four hundred years.
A Quick History Lesson ~ The Egyptians were the first to come up with the idea of adding a leap day once every four years to keep the calendar in sync with the solar year. Later, the Romans adopted this solution for their calendar, and they became the first to designate February 29 as the leap day.
The rules for determining a leap year ~ Most years that can be divided evenly by 4 are leap years. Exception: Century years are NOT leap years UNLESS they can be evenly divided by 400.
What are your chances of being born on leap day? About 1 in 1500.
WELL — there you are!!!