EXHIBIT 11.1 TRANSPORT CORPORATION OF AMERICA, INC. Computation of Earnings per Common Share THREE MONTHS ENDED NINE MONTHS ENDED SEPTEMBER 30, SEPTEMBER 30, ---------------------------- ---------------------------- 1998 1997 1998 1997 - ------------------------------------------------------------------------------------------------------------ Net earnings $ 3,940,000 $ 2,389,000 $ 7,454,000 $ 5,451,000 - ------------------------------------------------------------------------------------------------------------ Average number of common shares outstanding 6,714,611 6,578,579 6,699,019 6,561,448 Average number of common shares outstanding, non-detachable put 1,200,000 0 400,000 0 - ------------------------------------------------------------------------------------------------------------ Average number of common shares outstanding, including non-detachable put 7,914,611 6,578,579 7,099,019 6,561,448 Dilutive effect of outstanding stock options, warrants and non-detachable put 310,661 149,910 160,362 169,469 - ------------------------------------------------------------------------------------------------------------ Average number of common and common equivalent shares outstanding 8,225,272 6,728,489 7,259,381 6,730,917 - ------------------------------------------------------------------------------------------------------------ Basic earnings per share $ 0.50 $ 0.36 $ 1.05 $ 0.83 ============================================================================================================ Diluted earnings per share $ 0.48 $ 0.36 $ 1.03 $ 0.81 ============================================================================================================