Organizations: Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA · Department of Urban Studies and Planning, Massachusetts Institute of Technology, Cambridge, MA, USA · Center for Computational Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA · Mathematical Institute, University of Oxford, Oxford, UK · Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA · College of Urban and Environmental Sciences, Peking University, Beijing, China · Department of Urban and Regional Planning, University of Florida, Gainesville, FL, USA
New York City implemented the nation's first cordon-based congestion pricing program in January 2025, providing an opportunity to evaluate how system-wide urban mobility responds to large-scale pricing interventions. Because such policies generate spillovers across modes and locations, credible control groups are difficult to construct. We address this challenge using time series foundation models to generate probabilistic counterfactual demand forecasts with calibrated uncertainty. Applying this framework to bus, subway, and aggregate trip volume data, we find that post-policy bus and subway ridership increased significantly relative to expected no-policy demand, while overall travel demand decreased modestly. The effects are spatially heterogeneous: while reductions in overall travel demand are concentrated within the Congestion Relief Zone, transit gains extend beyond Manhattan's core. Socio-demographic analyses further reveal uneven adaptation across neighborhoods, highlighting spatial equity implications. Our framework provides a scalable approach for the uncertainty-aware evaluation of system-wide urban interventions when clean control groups are unavailable.