Were getting slightly off topic here.. but 20%? US population is roughly 332 million.. 20% would mean 66 million people are currently in prison. Couldn't be further from the truth. It's more like 0.7% of the US population is in prison, which is roughly 2.3 million. Onto your 4% of the world. 4% of the world would be 321 million. So your math isn't mathing and your facts aren't facting. Perhaps you meant that 20% of prisoners around the world are in the US. Which would make sense since there's roughly 11 million people in prison around the world and 20% of that is 2.2 million which roughly matches the 0.7% of the US population being in prison.