There is another whole population of slaves this graphic fails to mention.

In the USA about 1 million people are imprisoned. Laws in the USA require the captives to work. Maximum wage is under $1/hour. Most of these prisoners make much less, about $1/day.

There are over 1 million slaves being used for forced labor in the United States of America, the land of the free, by government agencies.

This is true slavery. Regardless of why the slaves were captured, the fact that they are forced to work for very little reward, and suffer dire abuses and punishments if they refuse, is the definition of slavery.

In September of 2016 there was a nationwide strike by government slaves. The wholly owned media probably never mentioned it to you. Many people were severely punished for participating in the strike, because organizing any kind of group at all is considered a high security threat, and chargable as a crime.

Even those who were not charged with new crimes suffered torture, such as confinement to solitary, reduction of rations to 'nutraloaf' a tasteless cake of some kind supposedly sufficient to keep you alive, 1 cake per day, and various other abuses, such as being strapped into a restraint chair 24 hours a day, rectal feeding, restrictions on visits from loved ones, phone calls, fines, and on and on.

If you have never been kept in a cage and had your every movement and bodily function watched under threat, you can hardly imagine the severity and subtlety the keepers can inflict without supervision, due process, or access to counsel.

Do not forget government slaves. In some ways, these people, up to 25% of which are innocent of the charges against them, but who were coerced into accepting a plea bargain, are victimized worse than other slaves. They are kept in cages, fed swill, and psychologically abused in addition to other damage they suffer.

I don't know how many captives are kept in other countries and forced to work, but one slave in the world is too many. 1 million in the land of the free is an abomination.