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Increases in VMT can lead to negative externalities including congestion, which 2 occurs when demand in the form of vehicles entering a roadway reaches a critical point 3 such that an additional vehicle causes all vehicles to slow down below free-flow speeds. 4 VMT is an example of a derived demand–one typically does not consume VMT with 5 the intention of directly benefiting from going to point A from point B, but rather takes 6 trips from B to A in order to access a bundle of goods or services: thus, VMT demand, 7 and therefore congestion, is strongly correlated with macroeconomic cycles. This paper 8 uses time series data from 87 US cities between 1982-2009 to examine the determinants 9 of congestion, including macroeconomic cycles, industry mix, and public interventions. 10 This research finds that urban areas with large percentages of construction jobs tend 11 to have lower levels of congestion. Additionally, it finds that public transit does not 12 have a statistically significant long term effect on levels of congestion across the US. 13