Professional football was the most popular sport in the United States for the ninth consecutive year, according to a 2011 poll by Harris Interactive. The National Football League, NFL, is, by far, the leading professional football league, with tens of millions of Americans tuning in every Sunday to watch their favorite teams play. Salaries for NFL players have increased dramatically as the game has gained in popularity, and salaries for NFL officials also got a boost in late 2012 when the NFL Referees Association signed a new contract with the league.