Interesting article on vacation time.
The bottom line is that many Americans do not take their earned vacation time.
In my experience of both myself and people that I know is most that have set use or loose vacation time generally use it.
How much vacation time I have at the end of the year determines my last work day for the year,. If I do not use a vacation day then I am basically working for free.
Those who vacation time can carry over and or they can sell that vacation time back generally do not take all of thier time. They save it for "what ifs" or extra income.
That worked very well for DH this year. Because he had so much accrued time he was able to take a lot of time off for family issues this week and still has enough to be off all of this week and all of Chistmas week.