U.S. Major Air Carriers On-time Performance
U.S. Major Air Carrier Domestic On-time Arrival Performance (monthly data, not seasonally adjusted)
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The share of flights arriving on time is a measure of service quality. Not only is this indicator strongly seasonal, but the data also reflect the effects of weather. From 1998 to 2008, 20.3% of flights were delayed, 2.1% were cancelled, and 0.2% were diverted. These data only cover major airlines, which are required to report delays.
| Flight On-Time Performance | Aug-08 | Aug-09 |
|---|---|---|
| Number of scheduled flights | 342,199 | 311,823 |
| Percent change from same month previous year | -4.94 | -8.88 |
| Percentage of flights arriving on-time | 78.68 | 80.34 |
| Difference from same month previous year* | 6.97 | 1.67 |
* Current
month minus same month previous year.
NOTES: The current value is compared to
the value from the same period in the previous year to account for
seasonality. Data are available for those carriers that had at least 1% of
domestic enplanements in the previous year. The last 25 months of data include
only carriers that reported in each of the last 25 months to retain
comparability. Earlier data includes all reporting carriers.
A scheduled operation consists of any nonstop segment of a
flight. The term "late" is defined as 15 minutes after the
scheduled departure or arrival time. A cancelled flight is one that was not
operated but was listed in a carrier's computer reservation system within
seven calendar days of the scheduled departure. A diverted flight is one that
left from the scheduled departure airport but flew to a destination point
other than the scheduled destination point.
SOURCE: U.S. Department of Transportation, Research and Innovative Technology Administration, Bureau of Transportation Statistics, Office of Airline Information, Flight Delays at-a-Glance, available at http://www.bts.gov/programs/airline_information/ as of October 2009.
