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Fig. 3


Ratios of the annual sunspot numbers: a) the ratio of WSN to GSN; b) the ratio of WSN-S to GSN-S; c) the ratio of WSN to WSN-S; d) the ratio of GSN to GSN-S. The vertical dashed line indicates the period when R. Wolf started his observations. Horizontal dotted lines depict the mean ratios before and after that date. Details of statistics are collected in Table 1.

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