Our Wallets expose our Hearts:

in 2008, traffickers made an estimated $31 billion buying and selling. In the same year, approximately 0.5% of this figure was spent by the GLOBAL community to combat human trafficking. ~ UNIAP

 To help that number sink in here are some other statistics.  McDonald's on average makes $21 Billion a year.
155,000,000 is .5% of 31 Billion.  That's also about the same amount that people spent on Halo 3 on it's release day.  Comparatively, The Dark Knight made 155 million in it's first weekend. 

About a week ago Avatar passed $550 million in ticket sales domestically.

The weighted average global sales price of a slave is calculated to be approximately $340, with a high of $1,895 for the average trafficked sex slave, and a low of $40 to $50 for debt bondage slaves in part of Asia and Africa.

The money spent on Avatar in a month could have freed 290,237 trafficked sex slaves.  The same amount could have purchased 11 Million slaves out of their debt bondage working conditions.  There are believed to be roughly 29 million slaves world wide.