Cohort progression — Haldens SK
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 freestyle50 breaststroke100 freestyle50 backstroke100 butterfly100 breaststroke100 backstroke200 freestyle
50 m butterfly men · 25 m pool
X: swimmer age in season · Y: median season-best time
born 2009 born 2008 born 2007