We get 15 days per year and the unused days carry over to the next year. When I was single, I hardly used any, now I average 9 per year. Some are used for when the kids are home from school sick (my wife works as well), some are for the days when my back is acting up and a few are 'mental health days', put aside just for me on those days (usually the summer months when we are really rocking at work) when I'm just too burned out from one too many domestic dispute or the plain old heavy work load to function as a professional.
Scott W.