Technology makes it really, really easy to make it so my grading time is absolutely minimal. So that gives me 12 weeks in the summer plus 2 weeks Christmas, 1 week Spring Break, .6 weeks Thanksgiving, .6 weeks fall break, MLK day, Labor Day, President's day, and then 10 school days off each year.
So it's more than 4 months actually. Not going to complain :).