Cohort progression — Stowarzyszenie SIG NOVUM
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 butterfly50 freestyle100 breaststroke50 backstroke100 freestyle100 backstroke50 breaststroke100 medley100 butterfly200 medley200 breaststroke200 freestyle
50 m butterfly men · 25 m pool
X: swimmer age in season · Y: median season-best time
born 2011 born 2008