This '400,000 prostitutes' figure seems to have originated from Hydra e.V., a prostitutes association [1]. It is at least three years old and seems to include p

This '400,000 prostitutes' figure seems to have originated from Hydra e.V., a prostitutes association [1]. It is at least three years old and seems to include part-time prostitutes as well. Generally, it seems to be an upper bound. [1] http://www.bmfsfj.de/BMFSFJ/root,did=132012.html http://www.bmfsfj.de/BMFSFJ/root,did=132012.html (German)