Fig. 1

Disk-area coverages by sunspots (upper panel) and solar faculae (middle panel) as well as the S-index (lower panel). The daily disk-area coverages are determined from the KP/512 (black dots), KP/SPM (red dots), and SOHO/MDI (blue dots) full-disk continuum images and magnetograms. The daily S-index (black dots in the lower panel) is calculated from the Sac Peak Ca II data. Magenta curves are the annually averaged data.
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