The company flew 9.2 billion revenue passenger miles (RPMs) in August, which is a 2% decrease from its August 2012 total of 9.4 billion RPMs, and 8% lower than the 10 billion RPMs in July 2013. A revenue passenger mile is one paying passenger flown one mile.
The company's available seat miles (ASMs) dropped since the previous month, but the August number was higher than it was a year ago. Southwest reported 11.3 billion ASMs last month, compared to 11.9 billion in July and 11.1 billion in August 2012. An available seat mile is one seat (empty or full) flown one mile. ASM is often referred to as the airline industry's measure of capacity.
In terms of occupancy, Southwest saw its monthly load factor clock in at 81.3%, a 2.9-percentage-point decrease from August last year, and a 2.2-percentage-point decrease from the previous month. Load factor is the percentage of a plane filled with paying passengers. It is calculated as Revenue Passenger Miles/Available Seat Miles.
The company, which also owns AirTran Airways, said that passenger revenue for every seat flown one mile rose 4% compared with August 2012. That follows an increase of 4% to 5% for July.
The airline also tallied 112,448 trips flown in August, down 3.9% from the same month last year, and a 4.2% decrease from July 2013. So far in 2013, the company has flown 891,956 trips, 3.7% lower than the year-ago number.
-- Material from The Associated Press was used in this report.
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