The reduction corresponds very closely to the number of concealed handgun licenses issued.
Urban areas benefit the most from concealed-carry laws.
The benefits of concealed guns are not limited just to those who carry them for self-defense. Arming older people not only may provide direct protection to these children, but also causes criminals to leave the area. That, from the mainstream media and many of our politicians. But this is an emotional response, wholly unsupported by the facts. The possibility exists that attempts to outlaw guns from schools, no matter how well meaning, may have produced perverse effects.