Yearly (1700-2008) data on sunspots from the National Geophysical Data Center.
Number of Observations - 309 (Annual 1700 - 2008) Number of Variables - 1 Variable name definitions:: SUNACTIVITY - Number of sunspots for each year The data file contains a 'YEAR' variable that is not returned by load.
The original dataset contains monthly data on sunspot activity in the file ./src/sunspots_yearly.dat. There is also sunspots_monthly.dat.
This data is public domain.