Monthly mean relative sunspot numbers from 1749 to 1983. Collected at
Swiss Federal Observatory, Zurich until 1960, then Tokyo Astronomical
Observatory.
Usage
sunspots
Arguments
Format
A time series of monthly data from 1749 to 1983.
See Also
sunspot.month has a longer (and a bit different) series,
sunspot.year is a much shorter one. See there for
getting more current sunspot numbers.