Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suicides committed with a gun, is most highly correlated with survey-based estimates. It is the best choice for use in cross-section analysis of the effect of gun prevalence on crime patterns across states and larger counties.

Analysis of this proxy measure for the period 1979–1997 demonstrates that the geographic structure of gun ownership has been highly stable. That structure is closely linked to rural tradition. There is, however, some tendency toward homogenization over this period, with high-prevalence states trending down and low-prevalence states trending up.