Select the Correct Statistical Test

A researcher is interested in differing interventions designed to reduce racist graffiti in an inner city area. He recruited nine neighborhoods that have a problem with racist graffiti and asked members to monitor the frequency, location, and content of racist graffiti. After four weeks of baseline recording, a six week sensitivity training workshop was begun. Community members continued to monitor the frequency, location and content of any racist graffiti during this time, yielding data for 10 consecutive weeks, 4 prior to workshops and 6 after workshops began. The researcher now wants to analyze his data comparing the frequency and location of the graffiti before the workshop and after the workshop. What statistical technique would you advise?