Point taken. While I also feel like delineating by regions in the US might be smart to some extent, the states are somewhat coupled to each other due to federal

Point taken. While I also feel like delineating by regions in the US might be smart to some extent, the states are somewhat coupled to each other due to federal programs and such. But yeah, you're probably right about it not helping since states have widely varying cost of living. Regardless, even if you do delineate by geography, excluding populations within a population is still "lipping your bad statistics to push up your mean.