WASHINGTON (AP) — The U.S. airline industry is slowly adding jobs, although not all carriers are growing.

The Transportation Department said Thursday that passenger airlines employed the equivalent of 383,610 full-time workers in March, up nearly 1 percent from a year earlier. It was the fourth straight monthly gain.

United had the most workers, 80,694, but that was down 2.1 percent. Southwest and its AirTran Airways subsidiary shrank by 1.4 percent.

Delta added the most jobs, followed by US Airways, American and JetBlue. Two smaller carriers, Spirit Airlines and Allegiant Air, grew fastest in percentage terms, both posting double-digit gains.

Several regional airlines added jobs including SkyWest, Republic and Mesa. They fly smaller planes for the big airlines.

The government counts two part-time employees as one full-time worker.

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