The various sections tabulate figures on Part I crimes, personal crime, property crime, clearances, the five command areas in Boston, homicides, crimes involving firearms, citywide drug arrests, drug control unit arrests, calls for service, and performance statistics. The fewest number of recorded Part I crimes since 1974 were recorded in 1992, with a 9-percent decrease over 1991 crime rates and a 17-percent decrease over 1990. There were also the fewest number of reported robberies since 1971 and the lowest property crime rate since 1974. Police recorded a 27 percent overall clearance rate for Part I offenses in 1991. Citywide drug arrests continued to decrease, while the overall number of calls for service fell by two percent from 1991 figures. The overall response time for Priority One calls averaged 7 minutes and 10 minutes for all priorities.