You are wrong. Communism has killed more people in the last hundred years then religion in the history of mankind.
You're telling me that in 80 years, Communists managed to kill more people than thousands of years of jihads, crusades, wars, skirmishes, sacrifices and persecutions?
That's right about the numbers for Communist homicide/genocide. If you count the Nazis and other horrific modern episodes of political genocide in the 20th-century by non-Christians, the numbers soar even higher.