Flaring activity measure β_100s as a function of stellar rotation period P_rot (median value, and 5th to 95th percentiles of the distributions in Fig. 8). The saturated branch at high rotation rates and β_100s ⪆ 5 yr⁻¹, and the drop in activity around the 10 d boundary resemble analogous distributions for X-ray, Hα, and surface magnetic field strength. The additional dimensions are age (different symbols representing three open clusters), and T_eff (colors). At the ages of Hyades and Praesepe, the T_eff ∼ 3500−3750 K stars are appear to be in the process of leaving the saturated branch, while the T_eff ∼ 3750−5000 K stars already showed low activity levels. See Sect. 4.5 for a detailed discussion.