If youâ€™re always complaining there are not enough hours in the day, today is your day.

Feb. 29 is a full extra day on the calendar that only comes around once every four years. Well, mostly.

Leap years exist because the daily rotation of our planet doesnâ€™t quite match up with Earthâ€™s orbit around the sun.

An Earth year is said to be 365 days long, but in fact, the planet actually takes 365.24 days to make a complete cycle around the sun. Without a leap year day every four years, we would soon be a full day out of sync with the calendar. Eventually, the start of the seasons would not match up with our calendar.

The Honor Society of Leap Year Day Babies says, without leap years, a person who lived to be 90 would see their birthday drift by three weeks over the course of their lifetime.

And just to complicate things further, leap years donâ€™t always occur every four years. They only happen on years that are divisible by four -- except for years that are both divisible by 100 and not divisible by 400. So, the year 2000 was a leap year, while the year 1900 was not. (It all comes down to that .24 of the 365.24 year length. Hooray for math!)

If that isnâ€™t confusing enough, try being a â€śleaperâ€ť â€“ that is, someone with a Feb. 29 birthday. Vancouver resident Mike Reid is one of them and he will tell you: it can be annoying.

Reid is turning 28 today -- although officially, heâ€™s only seven. He told CTVâ€™s Canada AM Monday that itâ€™s always been hard to decide when to celebrate his birthday since his actual birth date only comes around every four years.

But, he says, on his motherâ€™s insistence, he generally celebrates on March 1.

â€śMy mom thought it was weird to celebrate on the 28th when she was still in labour with me for so long, so March 1 is the day we celebrate it when itâ€™s not a leap year,â€ť he said.

Reid admits his birth date sometimes causes problems, such as when he wants to register for things online.

â€śSometimes, the leap year birth date is just not available as one of the options so Iâ€™ve run into problems with that,â€ť he says.

He also says heâ€™s been asked for ID from time to time and people have a hard time believing that Feb 29 is his real birthday.

The Honor Society of Leap Year Day Babies says thatâ€™s not unusual. Society co-founder Peter Brouwer recently told The Canadian Press â€śleapersâ€ť experience everything from webpage shutdowns to halted banking transactions.

But he added that things have improved in recent years, with computerized calendars now recognizing that every four years, there really is a Feb. 29.

With files from The Canadian Press