Transportation Networks and the Geographic Concentration of Employment

Abstract

Abstract This paper examines the effect of expanding transportation networks on spatial industrial growth across the United States from 1953 to 2016. I use a new methodological approach that applies network theory combined with a historic military map to address the two forms of endogeneity present in expanding transportation networks: route placement and construction timing. I find that Interstate counties experienced significant growth in employment and the number of establishments relative to non-Interstate counties. Growth rates are highest within two decades of receiving an Interstate. Results also reveal positive spillovers occurred in later decades among adjacent counties along the metropolitan periphery.