The years 1904 and 1907 saw a decline of mass movements, strikes and protests, and a rise of political terrorism. Combat groups such as the SR Combat Organization carried out many assassinations targeting civil servants and police, and robberies. Between 1906 and 1909, revolutionaries killed 7,293 people, of whom 2,640 were officials, and wounded 8,061. Notable victims included:

Answer this question based on the article: How many years did it take revolutionaries to kill 7,293 people?
3