Fig. 2: Policy Effects on NYC PM2.5 by Monitor.

A shows air-quality monitor locations (points) in the NYC Metropolitan Core-Based Statistical Area (CBSA). Points are shaded from white to blue by the size of the estimated decrease in PM2.5 during the Congestion Pricing policy from 6 January 2025 to 1 June 2025. Monitors outside the CBSA are shaded gray. B narrows into the extent of the Congestion Relief Zone (CRZ) in Manhattan. Estimates reflect monitor average treatment effects for fully specified models for the CBSA in A (Model 3) and for the CRZ in B (Model 9). Roads are shown in white. Block groups are shaded by population density in yellow, where gray indicates unavailable data. Mapped in R with the ggplot2 and sf packages30,31.