…according to this article from The American. Thanks to Cafe Hayek (!) for bringing it to my attention. Here is a quote from the article (the comparison with NFL is a amazing to me):
The U.S. now has 125 professional opera companies, 60 percent of them launched since 1970, according to the trade group OPERA America. The U.S. has more opera companies than Germany and nearly twice as many as Italy. In the most comprehensive recent study, the National Endowment for the Arts found that between 1982 and 2002, total attendance at live opera performances grew 46 percent.
Annual admissions are now estimated at 20 million, roughly the same attendance as NFL football games (22 million, including playoffs, in 2006–07). In part, this reflects a shift toward seeing opera domestically. “Foreign opera destinations like Salzburg and Glyndebourne are more expensive, and more Americans are staying home—and probably feeling safer for it,” says Richard Gaddes, general director of the Santa Fe Opera in New Mexico.