Following a slight month-to-month drop in December, North American carriers' average on-time performance in January posted an even sharper decline of 7.4 percentage points month over month to an average of 71.7 percent, according to data from aviation analytics company Cirium.
All carriers that qualified for the January report posted declines except for JetBlue, which increased its on-time performance by 0.8 percentage points from December to 71.8 percent. Cirium credited January weather, which caused "thousands of flights" to be canceled and negatively affected scores.
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Delta Air Lines (80 percent) and United Airlines (78.6 percent) once again placed first and second, respectively. American Airlines dropped to fifth place from third last month, while Alaska Airlines (74.5 percent) and Southwest Airlines (74.3 percent) each moved up one spot.
Delta was the only North American carrier to rank on the global on-time performance list, in eighth place.
North American carriers in January canceled more than 25,600 flights compared with December's less than 4,750 cancellations.
Completion factors for January also dropped for the top five carriers compared with the prior month, though for December each carrier posted completion factors of at least 99 percent. Delta in January led with 98.4 percent, followed by Southwest at 98 percent and American at 97.4 percent.
A flight is considered on time if the aircraft arrives at the gate within 15 minutes of the scheduled arrival time.
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