Quantitative Trade with Ships

This paper highlights an underexplored margin of heterogeneity that shapes resilience to disruptions in global maritime trade - the differential reliance of countries and sectors on specific categories of vessels. We combine US bills of lading records with ship registry and AIS-based port call data to document new stylized facts on vessel deployment, including switching patterns across ships, country specialization in shipbuilding, and the composition of fleets serving different country pairs. Exploiting the 2016 Panama Canal expansion as a quasi-natural experiment, we further provide the first direct estimate for the elasticity of substitution between vessels across size classes. Building on the empirical evidence, we then introduce endogenous vessel choice into a quantitative general equilibrium trade model that features multiple transport modes and a global market for shipping services. The model allows us to quantify the trade and welfare effects of two recent policy proposals that target specific ship types, namely, fees for Chinese-built vessels entering US ports and the inclusion of the maritime transport sector in the EU Emission Trading System.