He analyzed sunspot records (and approximated records), comparing them to riots, revolutions, battles and war in Russia and seventy-one other countries for the period 500 BCE to 1922 CE. (A process known as historiometry.) He found that a significant percent of what he classified as the most important historical events involving large numbers of people occurred around sunspot maximum. Edward R. Dewey, founder of the Foundation for the Study of Cycles, analyzed and published his data in 1951 in the Foundation's publications. In a 1971 book Dewey described the "four components" of Chizhevsky's eleven-year cycle and their approximate lengths: 1) a three-year period of minimum activity characterized by passivity and autocratic rule; 2) a two-year period during which masses begin to organize under new leaders and one theme; 3) a three-year period of maximum excitability, revolution and war; 4) a three-year period of gradual decrease in excitability until the masses are apathetic. Dewey questioned Chizhevsky's theory because in Chizhevsey's data, the sunspot cycle height lagged about a year ahead his "mass excitability index."