Table 1-55,,,,,,,,,, Passengers Denied Boarding by the Largest U.S. Air Carriersa,,,,,,,,,, ,1990,1991,1992,1993,1994,1995,1996,1997,1998,1999 Boarded (millions),421,429,445,449,457,460,481,503,514,523 ,,,,,,,,,, Denied boardingb (thousands),,,,,,,,,, Voluntary,561,599,718,632,771,794,899,"1,018","1,081","1,024" Involuntary,67,47,46,51,53,49,58,54,45,46 Total,628,646,764,683,824,843,957,"1,072","1,126","1,070" a Data are for nonstop scheduled service flights between points within the United States (including territories) by,,,,,,,,,, "the 10 largest U.S. air carriers, i.e., those with at least 1% of total domestic scheduled-service passenger ",,,,,,,,,, "revenues (Alaska, America West, American, Continental, Delta, Northwest, Southwest, TWA, United, and US Airways).",,,,,,,,,, "Before 1994, carriers included both majors and national airlines, i.e., airlines with over $100 million in revenue.",,,,,,,,,, "b Number of passengers who hold confirmed reservations and are denied boarding (""bumped"") from a flight ",,,,,,,,,, because it is oversold. These figures include only passengers whose oversold flight departs without them; they ,,,,,,,,,, "do not include passengers affected by canceled, delayed, or diverted flights.",,,,,,,,,, ,,,,,,,,,,, "SOURCE: U.S. Department of Transportation, Office of the Secretary, Air Travel Consumer Report (Washington, DC: Annual ",,,,,,,,,,, April issues).,,,,,,,,,,,