The U.S. ranks 145th in slavery

According to the Global Slavery Index, 2014, an estimated 0.019% of all the people in the United States are held in slavery. That is enough to make the United States rank one hundred forty-fifth out of one hundred sixty-seven countries ranked in that category. Mauritania ranks first, with an estimated 4% of its people held in slavery.

Table taken from http://d3mj66ag90b5fy.cloudfront.net/wp-content/uploads/2014/11/Global_Slavery_Index_2014_final_lowres.pdf