The June on-time performance for North American carriers dipped 1.2 percentage points month over month to 73.2 percent following a drop in May to 74.4 percent, according to aviation analytics company Cirium.
Not every carrier posted a decline, however, as they did in May. American Airlines in June was up 4 percentage points month over month to 73.6 percent, but still landed in fourth place. Southwest gained 2.1 percentage points and moved up to sixth place. United improved by 1.4 percentage points and moved up to third from fifth place.
The carriers with the largest average month-over-month declines included strike-affected WestJet (down 5.6 percentage points), JetBlue (down 4.8 percentage points) and Air Canada (down 4.4 percentage points).
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Delta Air Lines, though dropping 0.9 percentage points month over month to an on-time performance of 80.1 percent, remained in first place for North America, and was the only carrier from the region to make the top 10 global on-time performance list, in eighth place.
North American carriers in June canceled 11,806 flights, slightly up from the 11,491 flights canceled in May.
Alaska Airlines led North American carriers with a 99.5 percent completion factor, followed by Delta at 99.2 percent and Spirit Airlines at 99.1 percent.
A flight is considered on time if the aircraft arrives at the gate within 15 minutes of its scheduled arrival time.
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