Florida found some clear patterns in the stats, such as:
"Income and Economic Output: The richer the state, the less likely people were to drive alone. Driving alone was negatively correlated with state income levels (-.46) and output per capita (-.41).
Class and Human Capital: States with higher percentages of college graduates (-.47) and the creative class (-.43) were less likely to have people driving alone. Driving alone was much more likely in states with large working class concentrations (.62)."