A 2004 governmental study, which involved 450 interviews, found that the children most at risk for sexual exploitation were girls between the ages of 12 and 18 who worked as street vendors or domestic servants, or who were homeless children or the victims of child trafficking. Such exploitation was most prevalent in areas in which the population and economy were in flux, such as border zones or towns on transportation routes or in mining areas. The study noted that most cases of sexual exploitation went unreported and recommended that the country strengthen its laws to protect children.[20]