As I asked before, "Maybe all of the crime in Apr hasn't been reported [to the statisticians] yet?"
But yeah, I think we’ve all noticed that no one shoots up gun shows, but gun free zones seem to be shooting galleries (schools, post offices...). I’m just surprised that convention planners don’t’ seem to track / publicize how their shows impact cities, in terms of bringing in hotel / restaurant customers, and whether crime goes up or down.