Cohort progression — Pihlavan Työväen Urheilijat
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 breaststroke100 freestyle50 freestyle100 breaststroke50 backstroke50 butterfly100 backstroke200 freestyle200 medley100 medley400 freestyle100 butterfly