1/10th of 1 percent
The percentage of the population born on leap day (Feb. 29).
5 hours, 48 minutes, 45 seconds
The amount the calendar would be off each year without adding a day to February in leap years. In 100 years without leap years, seasons would be off by 25 days.
The day in February when there is a role reversal and women ask men to marry them. The tradition is believed to have started in Ireland. In Scotland the Leap Year proposal also came with a fine for any man who turned down a proposal. This is not to be confused with Sadie Hawkins Day (Nov. 15), which was a creation of cartoonist Al Capp in his long-running comic strip Li’l Abner. In the cartoon, there was an annual Sadie Hawkins Day Race. If a woman caught a bachelor during that race, he had to marry her. The first mention of Sadie Hawkins by Capp was in a Nov. 15, 1937 strip. By 1952, Sadie Hawkins Day was reportedly celebrated on Nov. 15 by 40,000 venues.
The year the leap year rule was enacted through adoption of the Gregorian calendar, which was named for Pope Gregory.
The number of days it takes the sun to return to the same position as seen from Earth. That is known as a “tropical” year. Adding an extra day for leap year every four years compensates for the accumulation of the numbers after the decimal point in a tropical year.
Sources: Infoplease.com, enchantedlearning.com, Irishcentral.com