Relation between plage and sunspot areas for individual SC based on the data from the Ko (a), MD (b), and MW (c) archives, and from the CEA20 plage area composite (d). The symbols denote the mean values of the PDF matrices (as shown in Fig. 3). The dashed lines are power-law fits and are coloured according to the strength of the SC with the strength increasing from black for the weakest cycle, via dark blue, turquise, green, lime, orange, bright red to dark red for the strongest SC.