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A statistical analysis of a large data set of H-alpha flares comprisingalmost 1 single events that occurred during the period January 1975 toDecember 1999 is presented. We analyzed the flares evolution steps, i.e.duration, rise times, decay times and event asymmetries. Moreover, theseparameters characterizing the temporal behavior of flares, as well as thespatial distribution on the solar disk, i.e. N-S and E-W asymmetries, areanalyzed in terms of their dependency on the solar cycle. The main results are:1) The duration, rise and decay times increase with increasing importanceclass. The increase is more pronounced for the decay times than for the risetimes. The same relation is valid with regard to the brightness classes but ina weaker manner. 2) The event asymmetry indices, which characterize theproportion of the decay to the rise time of an event, are predominantlypositive (90%). For about 50% of the events the decay time is even more than 4times as long as the rise time. 3) The event asymmetries increase with theimportance class. 4) The flare duration and decay times vary in phase with thesolar cycle; the rise times do not. 5) The event asymmetries do not reveal adistinct correlation with the solar cycle. However, they drop during times ofsolar minima, which can be explained by the shorter decay times found duringminimum activity. 6) There exists a significant N-S asymmetry over longerperiods, and the dominance of one hemisphere over the other can persist formore than one cycle. 7) For certain cycles there may be evidence that the N-Sasymmetry evolves with the solar cycle, but in general this is not the case. 8)There exists a slight but significant E-W asymmetry with a prolonged easternexcess.Comment: 13 pages, 11 figure

Statistical analysis of solar H$\mathsf{\alpha}$ flares