Histograms of period distributions in three mass bins for clusters with an age ranging from 4 to 150 Myr. The clusters’ name and age are given in each panel. Left: 0.4–0.6 M_⊙, Middle: 0.6–0.9 M_⊙, Right: 0.9–1.1 M_⊙. The number of stars in each mass bin is indicated in the lower left corner of the panels.