How often do you experience a leap year?

One leap year (366 days) usually replaces every 4th normal year (365 days), except for the last year of three out of every four centuries. A leap year adds one more day to the month of February, which makes February have 29 days instead 28 days.

The correlation between dates and days of the week completely repeats every 400 years, with each 400-year period including 97 leap years.