“In 2003, the Times reported that ‘some 500 students’ were enrolled in ’30 or so improvisation and sketch-comedy classes’ at U.C.B. In 2011, New York had the figure at approximately eight thousand. The organization doesn’t reveal numbers (the better to avoid quibbling about not paying its performers), but one current employee let slip the latest tally: last year, U.C.B. trained twelve thousand students. That’s about five million dollars in revenue.”