Researchers examined all sports-related concussions reported to an emergency room for children ages 5 to 18 in the United States over the course of one year. The table below displays the number of concussions in each of the major activity categories. Concussion frequency by activity in children ages 5 - 18 Activity Frequency Bicycles 23,405 Football 20,293 Basketball 11,507 Playground 10,414 Soccer 7,667 Baseball 7,433 All-Terrain Vehicle 5,220 Hockey 4,111 Skateboarding 4,408 Swimming 3,846 Horseback Riding 2,648 Total 100,952 What proportion of concussions came from playing football