Increasing accessibility by public transport benefits local economy: the effect of a new metro line in Rome

Abstract

This study investigates the economic impact of Metro C, a major expansion of Rome's metro system. Using a difference-in-differences (DID) approach within a multiplicative framework, the research quantifies the impact of increased accessibility on local economic activities. The results show a statistically significant rise in the number of economic activities in areas affected by the new line. A mild decline in economic diversity suggests the emergence of spatial clustering of similar activities. A dedicated analysis of microenterprises, which represent the majority of the dataset, examines changes in employment and GDP associated with the new infrastructure. The observed zone-level correlation between accessibility gains and growth in economic activities also offers a basis for generalising the findings beyond the specific case of Metro C. Overall, the case study shows that public transport investments aimed at boosting sustainable mobility can also generate positive spillover effects on the local economic fabric.