Comparison between the rotation periods measured and validated in the K2 light curves, P_rot,K2, and the reference values from the Gaia DR2 and DR3 catalogues, P_rot,Gaia. The 1:0.45, 1:2.1 (dotted grey lines), and 1:1 (dashed black line) lines are shown. The mean correlation coefficient ρ̄ is colour-coded, and the dot size is proportional to the A_max[G] index. For readability, the ρ̄ values are colour-coded only in the 0 to 1 range.