Frontier Airlines posted the best on-time performance among the 11 major U.S. carriers for the month of July

, at 75.5 percent. It was followed by Southwest Airlines (75.2 percent) and Northwest Airlines (70.1 percent). American Airlines again ranked last among the 11, at 63.4 percent. Industrywide on-time performance in July was 69.8 percent, slightly ahead of June but well behind the 73.7 percent rate recorded in July 2006.