for more we have michael glendening with us chief executive of the korea future initiative which produced that report michael this has been going on for years now your team has a dollar figure on the size of this industry how is this happening undetected. there is a complex an interconnected network of criminality in china resulting in the sale of north korean women and girls victims of prostitutes 1st as little as $4.00 but the sheer scale of this means it's not on the tech to every year thousands of north koreans leave the country the majority are women and many of those are trafficked but it's very very hard for them to be public about their experiences in china because china will arrest detain and repack treat them. there's limits its international advocacy on the issue because one possible result of any kind of advocacy could be that there is that china response by clamping down on the border this would result in. a reduction in cross border treat and so many north korean families in the country are reliant on the trade for survival now help us clarify a little bit about something yo