[korethr]

The number of police officers in an area is only part of it. Said officers must also be permitted by the policies they operate under to take effective actions that stop or deter the thefts. You could have enough officers and vehicles to have a patrol unit every other block at all hours of the day, but if department policy is such that doing anything other than witnessing the theft and taking a report afterward results in getting fired, odds are, the cops aren't going to be stopping many thefts.