NOTE: Any city pair that was in the top 50 for any year from 1990 to 2004 is included. Only carriers reporting Airline Service Quality Performance data are included. Based on a dataset the includes only airports that were in the top 50 for any year from 1990-2004. Only flights with similar characteristics operated in consecutive years for the same month are included. Aggregates will be affected by changes in distance for the underlying flights.
SOURCE: U.S. Department of Transportation (USDOT), Research and Innovative Technology Administration, Bureau of Transportation Statistics (BTS), calculations using the following: USDOT, BTS, Airline Service Quality Performance data, July 2006.
