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We analyze the temporal distribution of sunspot groups for even and oddcycles in the range SC12-SC24. It seems that cycle 24 is a characteristic evencycle, although with low amplitude. The number of large sunspot groups forcycle 24 is relatively smaller than for the average of both even and odd cyclesSC12-SC23, and there is a deep decline of the large groups in the middle of thecycle. Temporal evolution of the sunspot groups of the even cycles isnon-synchronous such that the northern hemisphere distribution of groupsmaximizes earlier that the southern hemisphere groups. This leads to adouble-peak structure for the average even cycle. On the other hand, thedistributions of the sunspot groups of odd cycles maximize simultaneously. Weshow that this double-peak structure intensifies the Gnevyshev gap (GG) for theeven cycles, but is not its primary cause. On the contrary, we show that the GGexists for even and odd cycles, and separately on both hemispheres. We resampleall cycles to have equal number of 3945 days and study the difference in theevolution of average total group area and average group area of the even andodd cycles separately. The analysis shows that there is a decline in both totalarea and average area in the even cycles 1445 days (about four years) after thebeginning of the cycle, which is at least 99 % significant for both total andaverage area. The odd cycles do not have such a clear decline.

Temporal Distribution of Solar Cycle 24 Sunspot Groups: Comparison to Cycles 12-23