An Evaluation of Developments in the Airline Industry Since 2000

Since 2000, the airline industry has undergone many changes. Major carriers have disappeared as a result of a series of mergers, leaving four big airlines, American, Delta, United, and Southwest, controlling around 80 percent of U.S. domestic traffic. The unbundling of airline services has also proliferated, most prominently for checked bags, which often now require payment of a fee. A new group of ultra-low-cost carriers (“ULCCs”), including Spirit, Frontier, and Allegiant, offers very low