So, KPI wise you can make an argument that it is effective. I may not agree with that argument in that we (USA) spend a lot of money and impose a lot of restrictions on the general population to get there.
Crime has always been a "the sky is falling" kind of a thing even if it's literally one crime. We are more safe than we were in 2001 by any objective measure, whether or not that is "safe enough" is going to be different for everyone...
Is it down because of police action or because of changing demographics?