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Fig. 1
Upper panel: monthly averages of the sunspot numbers. We clearly see the 11-year sunspot cycle (from http://solarscience.msfc.nasa.gov/SunspotCycle.shtml). Lower panel: variation of the S-index as a function of time for the Sun (from Lockwood et al. 2007).
This figure is made of several images, please see below:
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