Measuring Maritime Disruptions: A Route-Based Index of US Import Exposure

Summary

We construct a monthly maritime pressure index that measures US import exposure to disruptions using public trade and vessel-traffic data. The index weights disruptions along shipping routes by the value of imports using those routes, showing which goods are exposed and where they enter the country. It peaked in January 2024, at about five times its 2022–23 average, as the Red Sea disruption coincided with drought restrictions at the Panama Canal. That episode exposed a broad range of nonenergy goods entering mainly through East Coast ports. The 2026 Hormuz disruption was narrower, concentrating pressure on energy imports and refining centers along the Gulf and West Coasts.