MADISON, WI (AP) -

A state audit says the Wisconsin Department of Health Services should create written policies to guide how it selects housing for sexually violent offenders in the supervised release program.

The nonpartisan Legislative Audit Bureau released its report Thursday. It says DHS should take steps to save money on housing those in the program, including identifying additional firms willing to purchase and rent places for the offenders to live.

As of March 31, there were 33 people in supervised release. The state paid an average of $1,560 per month to rent 28 residences for them.

Between 2009 and 2012 the number of people on the program increased 22 percent. Costs under the program increased 33 percent over that time.