How many leap years are there in the whole world?

What do you mean by this? We'll always have leap years. We have leap years whenever the error in our calendar accumulates by 1 day so we don't fly ahead of the seasons and miss out on Summer. People still on Summer vacation when it's time to return to school will then be behind. We always skip leap years whenever the leap year error is off by a full day in our calendar to maintain the balance. In the future, leap years will cease as being 366 days by not adding the extra day February 29 into our calendar and February will always end on the 28 but one year, February will start ending on the 27 and the negative leap year will be 364 days long. The year will first have to be slightly shorter than 365 days.