  We use the historic record of sunspot groups compiled by the Royal Greenwich
Observatory together with the sunspot number to derive the statistical
properties of sunspot group emergence in dependence of cycle phase and
strength. In particular we discuss the latitude, longitude, area and tilt angle
of sunspot groups as functions of the cycle strength and of time during the
solar cycle. Using these empirical characteristics the time-latitude diagram of
sunspot group emergence (butterfly diagram) is reconstructed from 1700 onward
on the basis of the Wolf and group sunspot numbers. This reconstruction will be
useful in studies of the long-term evolution of the Sun's magnetic field.
