Antidepressants are still the most consumed class of medication in the U.S., with 270 million prescriptions per year. But sales revenue has gone down, to $9.4 billion, from a 2008 peak of $12 billion. Lower-priced generics now account for 85% of prescriptions, and 40% of the market in terms of revenue, with branded pharmaceutical companies withdrawing from the antidepressant market as their patents expire.