Left: difference between the disc fraction of magnetic features derived from SDO/HMI observations with reduced spatial resolution and reconstructed magnetograms with PF^* (red upward triangles), PFL^* (blue rhombuses), LFL^* (green squares), and PF (light blue downward triangles). Each of the upper two panels corresponds to a different feature (as marked in each panel) identified with Method 1, while the bottom panel is for all features together. The dashed lines connect annual median values, while the dotted horizontal lines are for a difference of zero. The shaded surface in the lower panel is as in Fig. 15. Right: distribution functions of the residual disc fractions.