Figure 3 Development of Truck Ton-Mile Estimates,,,, Ton-miles (billions),,,, Year,1997 Base,1993 Base,, 1990,847.591,831.981,, 1991,866.723,850.761,, 1992,888.985,872.612,, 1993,926.681,909.614,, 1994,986.540,968.371,, 1995,"1,032.594","1,013.576",, 1996,"1,060.466","1,040.935",, 1997,"1,109.000","1,088.575",, 1998,"1,138.182","1,117.220",, 1999,"1,174.742","1,153.106",, 2000,"1,191.156","1,169.218",, 2001,"1,211.511","1,189.198",, 2002,"1,243.799","1,220.891",, 2003P,"1,251.223","1,228.179", Key: p = preliminary.,,,