Cohort progression — A6
Median season-best times of each birth-year cohort, overlaid by age — shows how consecutive groups developed at the same stage of training.
Event: 50 backstroke100 backstroke200 backstroke50 breaststroke100 breaststroke200 breaststroke50 butterfly100 butterfly200 butterfly50 freestyle100 freestyle200 freestyle400 freestyle100 medley200 medley400 medley