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Figure 2.


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Excerpt from Appendix 1 of Hoyt & Schatten (1998a) which contains a list of the observers they considered along with their properties. Column descriptions: (1) Observer number; (2) and (3) First and last years of recorded observations; (4) the number of observing days; (5) k′-factor; (6) the 1σ uncertainty of the k′-factor (based on multiple intercomparison paths before 1884); (7) the number of standard or secondary observers used to calculate the k′-factor; (8) observer name and/or primary location where observations were made. The dashed blue line indicates the demarcation between observers who were scaled directly to RGO and those who were scaled to RGO by daisy-chaining.

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