NOTE: Rail productivity data are only available
through 1999. Source data are indexes
with base years of 1997 (air), 1996 (business), and 1987 (rail). BTS reindexed these data so that 1991 is
the base year for all.
SOURCE: U.S. Department of Labor, Bureau of
Labor Statistics, available at http://www.bls.gov, as of October 2003. Business
sector-"Most Requested
Statistics." Rail-"Industry
Multifactor Productivity Data Table by Industry, 1987-1999." Air-"Multifactor Productivity Data For Air
Transportation."