Southwest Airlines Co said on Thursday that quarterly profit edged down as costs increased.

Net income dipped to $224 million, or 31 cents a share, in the second quarter, from $228 million, or 30 cents a share, a year earlier.

There were special items including costs tied to the integration of AirTran, which was acquired in 2011. Excluding items, profit was 38 cents a share, in line with expectations of analysts on average, according to Thomson Reuters I/B/E/S.

Quarterly revenue rose less than 1 percent to $4.64 billion, compared with $4.66 billion expected by analysts. Operating expenses rose 1.3 percent, even as fuel and oil costs fell 5.6 percent.