by Michael Sivak, Sivak Applied Research.
The latest data from the Federal Highway Administration on the amount of driving in the United States indicate that vehicle miles traveled (VMT) in March of this year decreased by 18.6% compared with March 2019. However, the decrease in VMT varied widely by states, ranging from 26.0% in Vermont to 8.7% in Wyoming. In this post I will present the results of a new analysis that examined the relationship between the decrease in VMT in individual states (and the District of Columbia) and whether those states were “blue” or “red.”
The data on political preference in March came from the Cook Political Report (which in turn were based on its 2020 Electoral College Ratings published on March 9). The Report lists each state as Solid Democratic, Likely Democratic, Lean Democratic, Toss Up, Lean Republican, Likely Republican, or Solid Republican. In the present analysis, the states were combined into three groups: Solid or Likely Democratic (N = 18), Lean Democratic, Toss-Up, or Lean Republican (N = 11), and Likely or Solid Republican (N = 22).
The main result is that the average decrease in VMT in the states that were Solid or Likely Democratic was 20.9%, while in the states that were Solid or Likely Republican the decrease averaged 15.4%. In the Lean Democratic, Toss Up, or Lean Republican states, the decrease was in between—16.8%.
Although the states with Democratic preference tend to be more urban than the states with Republican preference, the urban/rural difference does not fully account for the main finding. First, VMT in March on urban roads decreased by 19.3% compared with a decrease of 17.0% on rural roads—a smaller difference than the Democratic/Republican difference obtained in this analysis. Second, in both states on the two extremes of the decrease in VMT (Vermont and Wyoming) rural driving dominates urban driving.
It is likely that the obtained difference reflects, in part, the differential onset of stay-at-home orders due to the Covid-19 pandemic. For example, by March 23, out of the 9 states with statewide orders to stay home, 7 were Solid or Likely Democratic and only 2 were Solid or Likely Republican.
Michael Sivak is the managing director of Sivak Applied Research and the former director of Sustainable Worldwide Transportation at the University of Michigan.