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We have analysed the combined Greenwich and Solar Optical Observing Network(SOON) sunspot group data during the period of 1874-2011 and determinedvariations in the annual numbers (counts) of the small, large and big sunspotgroups (these classifications are made on the basis of the maximum areas of thesunspot groups). We found that the amplitude of an even-numbered cycle of thenumber of large groups is smaller than that of its immediately followingodd-numbered cycle. This is consistent with the well known Gnevyshev and Ohlrule or G-O rule of solar cycles, generally described by using the Zurichsunspot number (Rz). During cycles 12-21 the G-O rule holds good for thevariation in the number of small groups also, but it is violated by cycle pair(22, 23) as in the case of Rz. This behaviour of the variations in the smallgroups is largely responsible for the anomalous behaviour of Rz in cycle pair(22, 23). It is also found that the amplitude of an odd-numbered cycle of thenumber of small groups is larger than that of its immediately followingeven-numbered cycle. This can be called as `reverse G-O rule'. In the case ofthe number of the big groups, both cycle pairs (12, 13) and (22, 23) violatedthe G-O rule. In many cycles the positions of the peaks of the small, large,and big groups are different and considerably differ with respect to thecorresponding positions of the Rz peaks. In the case of cycle 23, thecorresponding cycles of the small and large groups are largely symmetric/lessasymmetric (Waldmeier effect is weak/absent) with their maxima taking place twoyears later than that of Rz. The corresponding cycle of the big groups is moreasymmetric (strong Waldmeier effect) with its maximum epoch taking place at thesame time as that of Rz.

The G-O Rule and Waldmeier Effect in the Variations of the Numbers of Large and Small Sunspot Groups