Southwest Airlines Co. says traffic fell slightly in January.
Passengers on Dallas-based Southwest and its AirTran subsidiary flew 7.25 billion miles last month, down 1.7 percent from 7.38 billion in January 2012.
The traffic figure released Thursday could have been worse -- boardings fell by nearly 4 percent, but the average trip was 2.2 percent longer, which improves the traffic number.
Despite less traffic last month, passenger revenue per available seat mile rose 2 percent from a year ago. For airlines, that's a closely watched statistic that measures revenue for every unit of production.
The statistic rose faster in early 2012 after a series of fare increases.