Baseball, football, basketball and hockey accounted for 73 percent of the 422 million spectators at sports events in the United States and Canada last year.
Baseball drew 28 percent, followed by football and basketball at 15 percent, and hockey at 14 percent.
Other sports in the study included horse racing (12 percent), auto racing (6 percent), golf (3 percent), soccer (2 percent), and tennis (1 percent).
College and minor league events were also included, with college sports drawing 21 percent of the overall spectators.
Some sports were measured for their 1999-00 seasons.
Attendance at North American sports events reached a booming 422 million last year with the four major sports accounting for nearly three-quarters of the total, according to a new study.
