Approximation of 11-year solar cycles

We propose to approximate every 11-year cycle of solar activity by a function with three parameters. The first parameter determines the cycle position on the time axis, the second one shows the length of the growth phase of the activity index, and the third one is the maximum of smoothed index value. Values of these parameters for cycles 8–23 do not contradict in general the cycle parameters similar in sense and obtained from observations by the conventional method.