I don't know the exact accrual rate, but basically I get three weeks vacation a year. You can only carry over 40 hours, so at the end of the year I'm usually scrambling to take some time off just to get down to 40. It's mainly because I tend to schedule time off around a weekend, like taking off Thursday or Friday and coming back Monday or Tuesday. This was the first year in a long time that I took an actual LONG vacation (week and a half off).