Wednesday is a day that does not show up on our calendars every year. It's leap year, which adds February 29 to the calendar once every four years.
To celebrate the day, here are a few fun facts about leap year:
- Why do we have a leap year? Leap years are needed to keep our calendar in alignment with the Earth's revolutions around the sun, according to Timeanddate.com .
- The probability of having a leap day birthday — or a birthday on Feb. 29 — is 1 out of 1,461 or .068 percent, according to a New York Times article .
- Many workers have annual salaries, earning a set amount of money per calendar year. However, since salaries are typically not adjusted for leap year, this means that during a leap year an employee will probably end up working one extra day for the same yearly salary, according to the New York Times article.
- Prisoners are really paying for their crimes during a leap year. In the eyes of the law, a year has 12 months instead of 365 days, so inmates sentenced during a leap year have to spend one extra day behind bars, according to a story in the Pioneer Press .
- Celebrities with leap day birthdays include motivational speaker Tony Robbins, rapper Ja Rule and musician Chris Conley. Find more celebrity birthdays on leap day .