U.S. airlines posted one of their worst January on-time performances ever, as winter storms pounded parts of the country.
One-third of all flights arrived late, including nearly half of all flights into Chicago's O'Hare Airport.
The rate of canceled flights was the second-highest ever, and reports of mishandled bags soared.
The Transportation Department reported the numbers on Tuesday.
There were 21 flights that were stuck on the tarmac for longer than federal rules allow, with most occurring during a Jan. 2 storm in Chicago. The government said 16 involved Southwest Airlines planes that took a long time to taxi from the runway to gates at Chicago's Midway Airport.
Overall, 67.7 percent of flights arrived within 14 minutes of schedule, which the government considers on-time. That's the third-worst January since the Transportation Department started keeping records two decades ago, beating only January 1996 and January 1999. A year earlier, 81 percent of flights arrived on time.
Hawaiian Airlines — insulated from most of the bad weather on the mainland — had the best on-time record at 92.8 percent.
The bottom three were ExpressJet, at 56 percent, JetBlue and American Eagle. ExpressJet and American Eagle operate smaller regional flights that are often among the first to be canceled during storms, and JetBlue has big operations in New York and Boston, which were hit hard by winter storms.
About 6.5 percent of flights were canceled.
The rate of mishandled bags jumped more than 50 percent. Passengers on American Eagle and ExpressJet were most likely to have a bag lost, delayed, damaged or stolen. Virgin America topped the bag-handling rankings.
The figures cover domestic flights operated by 14 airlines, including all the biggest ones. Some notable carriers aren't included in the figures, however, such as Spirit Airlines, Allegiant Air and Mesa Airlines, because they're considered too small for mandatory reporting.