We hear a lot of individual stories about Latin thriving in the USA, but here are some statistics. They are part of a longer New York Times piece which you can read here. Thanks to David Meadows and Explorator for the link.
The number of students taking Latin is down from the turn of the 20th century; in 1905 an astonishing 56 percent of American high school students studied it. But the number has increased since it hit bottom in 1976, said Richard LaFleur, a former president of the American Classical League. A 2002 survey by the Modern Language Association showed a 14.1 percent increase (to 29,835 from 26,145) in the number of college students taking Latin since 1998 (ancient Greek was up 27.2 percent - to 20,858 from 16,402 - in that same period), and 7,892 students took the Advanced Placement exam for Latin this year, up from 4,142 in 1995, according to the College Board.

The National Latin Exam has experienced perhaps the most growth. When it was first offered in 1977 approximately 6,000 students took it. This year 134,873 students did.