Comparison of linear correlations of rotational variation between SSI and two proxies; sunspot area (Figs. 8a and 8b) and Mg II index (Figs. 8c and 8d). The blue lines denote the correlation between SIM SSI and the proxies, the red lines denote the correlations between SATIRE-S modeled SSI and the proxies, and the magenta lines denote the correlations between SOLSTICE A/B SSI and the proxies. Overlaid black dotted lines denote the correlations between TIM TSI and the proxies, respectively. (a) Correlation of the 27-day mode between SSI and sunspot area (115–400 nm). (b) Correlation of the 27-day mode between SSI and sunspot area (400–1600 nm). (c) Correlation of the 27-day mode between SSI and MgII index (115–400 nm). (d) Correlation of the 27-day mode between SSI and MgII index (400–1600 nm).