Time series of Chandra HRC-I CRs of α Cen A (blue filled circles), α Cen B (red), and Procyon (green). One-sided error bars (from the flare-filtering method) indicate degree of variability where significant. Gray crosses to the left are averages of XMM-Newton CRs of B, scaled to HRC-I. The slanted yellow line corresponds to a decline of 3.5% per year post-2016 for Procyon.