The average price of a slave has decreased during the past 200 years, according to Kevin Bales. a leading abolitionist and the President of Free the Slaves, who has written several books about modern-day slavery. In 1809, the average price of a slave was $40,000 when adjusted to today's money. In 2009, the average price of a slave was $90, Bales says.
In 1850 it was difficult to capture a slave and then transport them to the US. Today, millions of economically and socially vulnerable people around the world are potential slaves. This "supply" makes modern-day slaves more inexpensive than they have ever been. Since they are so cheap, slaves today are not considered a major investment and thus not worth maintaining. Therefore if slaves get sick, are injured, outlive their usefulness, or become troublesome to the slaveholder, they are dumped or killed.
Modern slavery is directly connected to the global economy, as most slaves were forced to work in agriculture, mining, and prostitution. From these sectors, their exploited labor flows into the global economy, and into our daily lives.