We just don't know. The numbers of children involved in pornography and sex trafficking also are uncertain. Liss reported that the number of child pornography cases being investigated by the Justice Department has jumped from around 90 to 300 cases per year. There are few international sex trafficking cases involving children currently under investigation, but a lot of cases of interstate trafficking. Liss noted that Midwest states are particularly popular places for the recruitment of girls for the sex trade on both coasts.
Girls are the vast majority of victims of commercial sexual exploitation in most countries.
In the United States, however, the number of sexually exploited boys is believed to be very high, perhaps nearly equal to the number of sexually exploited girls. They get together and create their own groups for protection. There's not so much reliance on pimps. But there are boys being prostituted by their families, and there are boys being drawn into pedophile sex rings. They are abused and exploited.