Monthly Sunspot Numbers, 1749--1983
Monthly mean relative sunspot numbers from 1749 to 1983. Collected at Swiss Federal Observatory, Zurich until 1960, then Tokyo Astronomical Observatory.
A time series of monthly data from 1749 to 1983.
Andrews, D. F. and Herzberg, A. M. (1985) Data: A Collection of Problems from Many Fields for the Student and Research Worker. New York: Springer-Verlag.
require(graphics) plot(sunspots, main = "sunspots data", xlab = "Year", ylab = "Monthly sunspot numbers")