This post is looking at the body count of both political and economic systems. Every system is going to have a body count. That is a given because they both have to be forced in the beginning. Even capitalism was forced at first. I am looking at the history of both and those who pursed them.
Capitalism drove European Explores to our shores. They came here in pursuit of riches like gold, and spices which is what brought Christopher Columbus to the Indies in the Caribbean. What he found was humans in what we call America. He took back American Indians as slaves and a gift to the Queen of Spain. With that said let's look at Communism and slavery. There are many testimonies from people who were at the 1917 revolution in Russia. Also, there are folks who have survived Mao left testimonies behind.
Here are some links to look into:
Captislist Quest for Resources
Atrocities Against Native Americans
http://endgenocide.org/learn/past-genocides/native-americans/
If Communism Killed Millions, How Many Did Capitalism Kill?
https://eand.co/if-communism-killed-millions-how-many-did-capitalism-kill-2b24ab1c0df7
How and when did the capitalism era begin?
https://www.quora.com/How-and-when-did-the-capitalism-era-begin
Communism
https://www.britannica.com/topic/communism
YouTube Channel on Communism
https://www.youtube.com/channel/UCDyoUB9kJyWXPcv0uuLLNYg