  The parameter G, which is determined from the general number of sunspots
groups Ng according to the daily observations G=Sum(1/Ng)^2, is offered. This
parameter is calculated for the days when there is at least one sunspots group.
It characterizes the minimum epoch solar activity. Parameter G mounts to the
maximum during the epoch close to the minimal activity of sunspots. According
too the data of the sequence of sunspots group in Greenwich-USAF/NOAA
observatory format, observation data of Kislovodsk solar station and also daily
Wolf number the changes of parameter G during 100 years were reconstructed. It
is demonstrated in the paper that parameter G's amplitude in minimal solar
activity n is linked with the sunspot cycle's amplitude Wn+1. The 24th activity
cycle prediction is calculated, which makes W24=135(+/-12).
