Domestic U.S. airline passenger yield in December declined by 0.4 percent

year over year to 15.5 cents per mile, marking the largest monthly decrease since June 2007, according to the Air Transport Association. Defined as the "average price someone pays to fly one mile excluding government taxes and fees," yield also decreased on Atlantic and Pacific routes--by 3.7 percent and 0.5 percent, respectively--each for the first time since September 2003. Yield on Latin American routes rose by 4 percent, the smallest increase since April.