Racking up $616,090 in personal air travel as the president of Leucadia National (LUK) did last year is a pretty impressive feat, even by the high-flying standards of corporate executives. It’s particularly impressive given that Joseph Steinberg’s salary last year was $612,207, according to its recent proxy. So why should Leucadia’s investors care? An interesting article in yesterday’s New York Times gives a few good reasons. The article reported on a new study by Prof. David Yermack of New York University, which found a “dramatic almost shocking link between a company’s stock price and the use of corporate aircraft.” The stocks of companies that disclose the personal use of corporate aircraft drop 2 percent on average and more than 4 percent compared to market benchmarks, according to the Times. Yermack said that investors could “really clean up” by short-selling companies that freely hand over the keys to the Gulfstream.