Founded: 1964 as the Clipper Trucking Co. It became Spirit Airlines in 1992 after an employee vote.
Headquarters: Miramar, Fla.
Four largest bases: Dallas/Fort Worth, Fort Lauderdale, Las Vegas, Chicago
2011 net income: $76.4 million
2011 sales: $1.1 billion
Employees: 2,456 full-time employees in 2011