Cohort progression — Lubelski Okręgowy Związek Pływacki
Median season-best times of each birth-year cohort, overlaid by age — shows how consecutive groups developed at the same stage of training.
Event: 400 freestyle100 freestyle50 freestyle800 freestyle50 backstroke100 butterfly100 medley100 backstroke200 freestyle50 butterfly400 medley200 medley200 backstroke100 breaststroke200 butterfly