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The subject of this paper is the existence and stability of solar cycles withdurations in the range of 20-250 years. Five types of data series are used: 1)The Zurich series (1749-2009 AD), the mean annual International sunspot numberRi, 2) The Group sunspot number series Rh (1610-1995 AD), 3) The simulatedextended sunspot Rsi number from Extended time series of Solar Activity Indices(ESAI) (1090-2002 AD), 4) The simulated extended geomagnetic aa-index from ESAI(1099-2002 AD), 5) The Meudon filament series (1919-1991 AD) (it is used onlyparticularly). Data series are smoothed over 11 years and supercenturial trendsare removed. Two principally independent methods of time series analysis areused: the T-R periodogram analysis (both in the standard and "scanning window"regimes) and the wavelet-analysis. The obtained results are very similar. It isfound that in all series a strong cycle with mean duration of 55-60 yearsexists. It is very well expressed in the 18th and the 19th centuries. It isless pronounced during the end of the 19th and the beginning of the 20thcenturies. On the other hand a strong and stable quasi 110-120 years and~200-year cycles are obtained in all of these series except in Ri. In the lastseries a strong mean oscillation of ~ 95 years is found, which is absent in theother data sets. The analysis of the ESAI (1090-2002 AD) proved that the quasicentury cycle has a relatively stable doublet (~80 and ~120 years) or triplet(~55-60, 80 and 120 years) structure during the last ~900 years. An interestingfeature in all series is the existence of significant ~29-year cycle after thelast centurial Gleissberg-Gnevishev's minimum (1898-1923 AD). Most probably thedifferent types of oscillations in the sub-century and century period rangecorrespond to cycles of different classes of active regions.

The sub- and quasi-centurial cycles in solar and geomagnetic activity data series/v.3