Enjoy today – there won't be another one for four years

Sign up for a full digest of all the best opinions of the week in our Voices Dispatches email

Sign up to our free weekly Voices newsletter

Please enter a valid email address

Please enter a valid email address

SIGN UP

I would like to be emailed about offers, events and updates from The Independent. Read our privacy policy

Today, Ja Rule, the now almost middle-aged American rapper, celebrates his ninth birthday. And were Mr Rule not already married, a suitor could legitimately hold a fourth finger up to tradition and ask him for his hand. If he were to refuse, he would be obliged to pay his suitor a fine of anything from a kiss to a dozen pairs of gloves.

Today, you see, is a leap day, the intercalary anomaly that allows "leaplings" in their 80s to pretend they're in their 20s and single ladies of all ages to put a ring on it.

They have Julius Caesar to thank. Way back in 46 BC, he ditched the chaotic Roman calendar in favour of his own, Julian, calendar which, after later reforms, became the Gregorian calendar we use today. Sensible Caesar decided to align his calendar with the solar year, the time it takes Earth to orbit the sun. But Earth takes 365 days and about six hours to make its journey through space. A six-hour day at the end of each year would be silly so instead we add a whole, intercalary day every four years.

However, the Earth's orbit is actually 10 minutes and 48 seconds faster than 365 days and six hours, which is inconvenient. To keep things aligned, leap days come in years evenly divisible by four, except when they are also evenly divisible by 100, when they don't have a leap day, except when they are also evenly divisible by 400, when they do. That's why 1900 did not have a leap day while 2000 did. Got it?

Whatever, today's the day and all over the world an estimated four million people are blowing out candles (you have about one in 1,500 chance of being born on 29 February) while commitment phobic men with twitchy-fingered partners bulk buy gloves. At least they do in Denmark, apparently. The table-turning proposal purportedly started as a tradition in 5th century Ireland. Others trace it to 13th century Scotland, where Queen Margaret required a man who said no to soften the blow with a kiss, a pound or a silk gown.

It's not that great, being a leapling, your ability to defy age notwithstanding. Many websites won't allow you to enter 29 February as your date of birth. Some countries legally compel you to settle for 28 February, while others go for 1 March.

And while leapers get to celebrate today (happy birthday, Ja) we should all be commiserating. Is your employer paying you an extra day's wages this year? Thought not.