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Violent Crime: R^2 = 0.61
Murder: R^2 = 0.62
Interactive graph: https://plot.ly/~rwvalentine/3/
Data sources:
https://www.icpsr.umich.edu/icpsrweb/NACJD/discover-data.jsp
https://factfinder.census.gov/faces/tableservices/jsf/pages/productview.xhtml?pid=ACS_14_5YR_S0901&prodType=table