Methodology:

The Chronicle analyzed data from SFPD’s Crime Incident Reporting System , which tracks all incidents reported to police. The number of break-ins last year was slightly lower than what was published in SFPD’s COMPSTAT reports (31,322). The number of arrests was slightly higher than what the district attorney’s office has reported (517) and will probably continue to increase as more of last year’s incidents are cleared. To determine hot spots, The Chronicle counted the number of break-ins in every census block in the city. All incidents reported from the Hall of Justice were excluded from the geospatial analysis, because they most likely showed where the crime was reported, not where it occurred. Some break-ins reported from Golden Gate Park may also have imprecise geographic information. The Chronicle used California Department of Justice and U.S. Census Bureau data to determine car break-in rates in major cities.