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The Catalogues of the solar proton events [Logachev, ed., 1982-2016] provide the homogeneous data series of events with maximum intensity of > 10 MeV solar protons J ≥ 1 cm-2 s-1 sr-1 beginning from 1970 up to now. The event rates behavior is rather smooth: the total number of such events, relative to accumulated sunspot number, is almost constant in the solar cycles 21-23 and even slightly growing in the solar cycle 24. Contrary, the total number of the most powerful (GLE) events per cycle was constant within statistical errors in the cycles 21-23, and it fell abruptly in cycle 24. Considering the conventional sources of GLEs we found that production of GLEs by X-class bursts was 3 times less in cycle 24 than in cycle 23, while production of GLEs by the >1000 km/s halo-type CMEs was 5 times lower.

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