US Airways (UNKNOWN:LCC.DL) notched an all-time high in one of its key metrics for the month of May. The company said its load factor (i.e., the average passenger "occupancy" of its planes) increased to 85.8%, the best showing for any May in its history. That number was also 1.7 percentage points higher than the same month of 2012.

The load factor figure was one of a number of May metrics released by the airline. Revenue passenger miles came in at 5.85 billion, an improvement over May 2012's 5.53 billion. Available seat miles advanced by nearly 4% to 6.83 billion; the number for the same month last year was 6.57 billion. The total number of enplanements also grew, reaching nearly 5 million from the year-ago May's 4.7 million.

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