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Leap Year 2016: Why does February have 29 days every four years?

When is it, why does it happen and everything else you need to know about the leap year in 2016

When is it, why does it happen and everything else you need to know about the leap year in 2016

Why do we have leap years?

A leap year, where an extra day is added to the end of February every four years, is down to the solar system's disparity with the Gregorian calendar.

A complete orbit of the earth around the sun takes exactly 365.2422 days to complete, but the Gregorian calendar uses 365 days.

So leap seconds - and leap years - are added as means of keeping our clocks (and calendars) in sync with the Earth and its seasons.

Why does the extra day fall in February?

All the other months in the Julian calendar have 30 or 31 days, but February lost out to the ego of Roman Emperor Caesar Augustus.

Under his predecessor Julius Caesar, February had 30 days and the month named after him - July - had 31. August had only 29 days.

When Caesar Augustus became Emperor he added two days to 'his' month to make August the same as July.

So February lost out to August in the battle of the extra days.

Technically, a leap year isn't every four years

The year 2000 was a leap year, but the years 1700, 1800 and 1900 were not.

There's a leap year every year that is divisible by four, except for years that are both divisible by 100 and not divisible by 400.

The added rule about centuries (versus just every four years) was an additional fix to make up for the fact that an extra day every four years is too much of a correction.

Julius Caesar vs Pope Gregory

The Roman calendar did have 355 days with an extra 22-day month every two years, until Julius Caesar became emperor and ordered his astronomer Sosigenes to devise a better system in the 1st Century.

Sosigenes decided on a 365-day year with an extra day every four years to incorportate the extra hours, and so February 29th was born.

                                                                                Julius Caesar

As an earth year is not exactly 365.25 days long Pope Gregory XIII's astronomers decided to lose three days every 400 years when they introduced the Gregorian calendar in 1582.

The maths has worked ever since but the system will need to be rethought in about 10,000 years' time.

Is February 29 a bank holiday?

It's not - but there is a campaign to make February 29 a bank holiday.

Workers have realised that every leap year, they have to work one extra day for no extra pay.

If a person earns the national average salary of £26,500 a year, that works out at £2,208.33 per monthly payslip – which breaks down to £71.24 per day in a 31-day month but a daily wage of £78.87 in February.

This realisation prompted Karl Savage, who was a high school teacher from Maryland, to try and kick-start the “No Work on Leap Day Revolution” in 2008, when the extra day fell on a Friday.

What if you're born on February 29?

The chances of having a leap birthday are one in 1,461. People who are born on February 29 are referred to as "leaplings", or "leapers". In non-leap years, many leaplings choose to celebrate their birthday on either February 28 or March 1, while purists stick to February 29 for the occasion.

Some suggest those born before midday on February 29 should celebrate their birthdays on February 28, while those born in the afternoon and evening of the 28th should celebrate their special day on March 1 (St David's Day).

Those born around midday are less fortunate when it comes to picking a side.

About 4.1 million people around the world have been born on the 29th.

Pisces is the zodiac sign of a person born on February 29, and amethyst is the birthstone for this month.

Are you celebrating a birthday on February 29th? Majestic Wine is offering a free bottle of champagne (to those who buy six bottles).

Famous people born on a leap day

The chances of having a birthday on a leap day are extremely slim - the odds are one in 1,461 to be exact - and there's quite an eclectic mix of famous people born on the day.

John Byrom - Romantic poet

Pope Paul III - 16th Century pontiff

George Bridgetower - 19th Century musician

Ann Lee - leader of the Shakers

Gioacchino Rossini - Italian composer

Charles Pritchard - British astronomer

Sir Dave Brailsford - English cyclist and coach

Tony Robbins - Motivational speaker

Alan Richardson - composer

Darren Ambrose - English footballer

Ja Rule – rapper