3 paychecks in February

I get paid bi-weekly on Fridays and this year I get 3 paychecks in February. I was wondering how often that happens and with Excel's help I found that it happens every 56 years. I also found that a month with 3 paychecks will be 5-7 months later than the last month with 3 paychecks. In 2010 there will be 3 months with 3 paychecks.