Introduction
A leap year is a year that has an extra day, February 29, making it 366 days long instead of the usual 365 days. It occurs once every four years to synchronize the calendar year with the seasonal year.
Frequency of Leap Years
A leap year happens every four years, except for years that are evenly divisible by 100 but not by 400. For example, the year 1900 was not a leap year because it is divisible by 100 but not by 400. However, the year 2000 was a leap year because it is divisible by both 100 and 400.
Importance of Leap Years
Leap years are crucial for keeping our calendar in line with the Earth’s revolutions around the sun. Without them, our calendar would slowly drift out of sync with the changes in the seasons.
Examples
- 2020 was a leap year.
- The next leap year will be 2024.
- The last leap year was 2016.
Case Study: Year 2000
The year 2000 was a leap year because it is divisible by both 100 and 400. This unique occurrence happens only once every 400 years, making it a significant event in the calendar.
Statistics
On average, there are 97 leap years every 400 years. This adjustment ensures that the calendar year is within about 26 seconds of the solar year, which is the time it takes for the Earth to orbit the sun.
