Once every four years we gain an extra 24 hours – this day, February 29th. So for people complaining they’ve never got enough time, this could be the opportunity for them! But why does it only happen once every four years, and what’s the explanation behind it?

Well, the Gregorian calendar (introduced in 1852) puts one year on earth as being 365 days – the time it takes for the Earth to orbit the Sun. However, more accurate calculations have shown that in fact the time taken measures at 365.24 days per year.

For this reason, an extra day every fourth year is added on to keep the seasons in sync. Without it, we’d very soon be a full day out of time with our calender.

All the other months in our year, of course, have either 30 or 31 days. It wasn’t always that way, though. Under Roman emperor Julius Caesar, February had 30 days, and August had only 29. When Caesar Augustus became emperor, however, he added two days to his namesake month, and February paid the price.

To make things even more complicated, not every fourth year is strictly predictable as a leap year. It’s all to do with the 365.24 not being a 365.25. The rule goes that every fourth year is a leap year, except for years which are divisible by 100 but NOT divisible by 400. Complicated stuff!

And if you’re one of those people born on February 29th, well it seems life can be a little complicated. So-called “leapers” have reported problems in the past when filling in forms online – sometimes the date doesn’t even register. According to website About.com, some 0.07% of the world’s population were born on February 29th.

In terms of leap year traditions, probably the most famous one is that of women proposing to men. Legend has it that in Dark Ages Ireland, St Bridget complained to St Patrick about men’s tardiness in their proposals. St Patrick is said to have given February 29th as the day on which women could take the initiative. So go on girls – don’t hesitate!