[Restorer]

Some of the numbers I've seen for the Mongol invasions:

Population of China reduced by half in 50 years, from 100M to 50M.

5M killed in Central Asia.

5M killed in Russia and Eastern Europe.

5 to 7M killed in Persia.

A little known fact: The Mongols for a while had a state policy of killing the entire population of China, with the idea that this would give them a lot more ground to pasture their flocks on. Until a Chinese official pointed out that hard-working Chinese peasants are a much more valuable crop per acre than sheep or horses.

[Ditto]

According to Wikipedia only about 100 M was the number of people under their control at the height of their Empire.

Yes, they killed a lot, it took half of the Euroasian land mass to even have 100 million. That's a lot of people.

The 5 million for Central Asia is probably about right, but keep in mind, for some reason, they really didn't like Muslims much. They were much more "civilized" around Christians and Buddhists.