| This thesis explores the relationship between annual federal and state spending on the national Interstate Highway System (IHS) and an annual measure of performance of this infrastructure asset--traffic congestion. Traffic congestion is operationalized as the percent of miles in a state's Interstate highway network operating above pre-designed capacity thresholds. A fixed effects regression analysis is conducted to assess the association between Interstate congestion mitigation, capital as well as maintenance expenditures, and Interstate congestion between 1999 and 2008. The paper finds a small, yet statistically significant, negative relationship between government spending on capital improvements on the Interstate and Interstate congestion; and a smaller, but also statistically significant, positive relationship between Interstate highway maintenance spending and Interstate congestion. There is no statistically significant relationship found between congestion mitigation spending and Interstate traffic. This paper concludes that the way in which public money was spent on the Interstate Highway System did not have a strong association with improved performance of the network in the short run. It is possible, however, future studies of public spending on the Interstate Highway System using more years of data could facilitate an analysis with additional year lags. Such an approach might, in turn, reveal stronger relationships between Interstate spending and reduced traffic congestion over the long run. |
