“I was at the bank in 2006 and the cashier told me that the ID number I had provided her didn’t look ‘right’. That’s when it hit me that my birth day was unlike other people’s; mine only comes once in four years,” recalls Ace Matiwane. He turns 36 on leap day, 29 February 2020.

“I’ve only had nine birthdays since birth, and I guess that makes me nine years old right?” he says, giggling softly.

Ace is one of only four million people in the world who are leap year babies, or ‘leapers’ as they are also known. A leap year has 366 days, instead of the usual 365, with an extra day added in February and only comes once every four years.

You may be asking yourself, who created the calendar and did they really have to include a 29th day in February? Scientists will tell you it’s more complicated than just adding an extra day for the fun of it.

Why do we have a leap day?

Earth actually takes more than 365 days to orbit the sun; it takes 365 days, five hours, 48 minutes, and 46 seconds to be exact. The Egyptians were among the first to identify the need for a leap day to account for the extra time, but their efforts didn’t bear any fruit. It was only in 46BC, when Julius Caesar revamped the Roman Julian calendar, that the change happened.

Caesar’s calendar considered this difference. It had 365 days and 12 months, adding an extra year (or a leap year) every four years to help sync the calendar with the solar year (the length it takes for earth to orbit the sun).

Caesar helped bring the calendar even closer to the solar year but his model wasn’t quite accurate. It missed the mark by 11 minutes and 14 seconds every year, which drifted off course by a day every 124 years and got worse as the centuries went by. His calendar was also not in sync with the seasons, and so people would often sow their crops at the wrong time.

It was in 1582 that Pope Gregory XIII came to the rescue with a revised Gregorian calendar, which now is in standard use all over the world.

The Gregorian calendar gets the thumbs up

Pope Gregory XIII’s model also had a leap year every four years, but there was an exception. Century years evenly divisible by 100 and not by 400 weren’t leap years. For example, the years 1700, 1800 and 1900 were not leap years. This slight difference between the two models helped bring the calendar year closer to the solar year, with an average of 365.2425 days.

This calendar is now used globally because of its similarity to the solar year, even though it’s also not perfect. Experts calculate that it also will gain one extra day in error, but not in the next 3000 years.

Do leapers celebrate their birthdays when it’s not leap year?
Some leapers choose to celebrate their birthdays on the 28^th because they were born in February. Others keep their celebrations to the 1^st of March, because they would’ve been born in March had it been a normal year.

“Most people think I don’t celebrate mine yearly but I do, either on the 28^th of February or 1^st of March. It depends on my mood really,” says Ace, adding that he wins either way.

Do women really propose on leap days?

This tradition dates back to the 5^th century in Ireland. Legend has it that St Brigid was receiving messages from single women complaining that their men were ‘too shy’ (or maybe ‘altar-phobic’) and took too long to propose to them. She pleaded with St Patrick to grant women permission to propose. St Patrick allowed women to propose once every seven years but St Brigid was still unsatisfied. Eventually, women were allowed to propose every leap day. This tradition is now known as ‘Ladies Privilege’.

The leap year is not just a random year; it was carefully planned and calculated over centuries. Experts do, however, note that imperfections in the Gregorian calendar will have to be addressed in about 10,000 years’ time, once the calendar has gained three days in error. In the meantime, if you’re Facebook friends with a leaper and you get a notification on the 29^th that it’s their birthday, please do write something nice on their wall – it only comes once every four years!

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