How often do couples who live together have sex?

I know the answer to this question is on a case by case basis, but just out of curiosity, if you live with your boyfriend, how often do you have sex? Again, I realize the answer to this question depends on a number of factors. I would like to ask simply because I feel as though couples feel as though they should be having sex all the time, but things are a little more complicated when you live together. In addition, it really varies from couple to couple.