Figure 1,,,,,
Highway Vehicle Trends: 1989–1999,,,,,
,,,,,
Index: 1989 = 1.0,,,,,
Year,Passenger cars,2-axle 4-tire trucks,Motorcycles,Buses,Commerical trucks
1989,1.00,1.00,1.00,1.00,1.00
1990,0.99,1.05,0.96,1.00,1.00
1991,0.95,1.15,0.95,1.01,0.99
1992,0.94,1.24,0.92,1.03,0.97
1993,0.95,1.31,0.90,1.05,0.98
1994,0.95,1.37,0.85,1.07,1.06
1995,0.95,1.43,0.85,1.10,1.08
1996,0.96,1.50,0.88,1.11,1.13
1997,0.96,1.53,0.87,1.12,1.14
1998,0.98,1.55,0.88,1.14,1.24
1999,0.98,1.64,0.94,1.17,1.25

"SOURCES: 1991–1995: U.S. Department of Transportation, Federal "
"Highway Administration, Highway Statistics Summary to 1995 "
"(Washington, DC: 1997),  tables MV-201 and VM201a."
"1996–1997: ____. Highway Statistics 1997 (Washington, DC: 1998), "
table VM-1.
"1998–1999: ____. Highway Statistics 1998 (Washington, DC: 2000), "
table VM-1.