According to the Amadeus Worldwide Estimate of Ancillary Revenue for 2011, that’s a 43.8 percent increase over the year before. “Half of the increase is a result of the airlines doing better year over year,” said Jay Sorensen, president of IdeaWorks, which co-authored the report. “The other half is because the airlines are clearly becoming better retailers, increasing revenues of existing activities and adding more of them.” According to Sorensen, seven U.S. airlines — Alaska, American, Delta, Hawaiian and US Airways, along with the still-separate operations of Continental and United — will earn an estimated $12.5 billion, up 87 percent from 2010. Get the full story at msnbc