Back in 2000, this was the genre breakdown at the box office:

Action/Adventure: 35%
Comedy/Romantic Comedy: 25%
Drama 23%
Horror/Thriller: 13%
Other: 4%

This is what that looks like today:

Action/adventure: 60%
Horror/thriller: 17%
Drama: 12%
Comedy/Romantic Comedy: 7%
Other: 4%

HT Lucas Shaw @ Bloomberg