Unit values of US imports net of tariffs turned negative in April 2025, according to European Central Bank analysis published this week—a concrete marker for compliance teams tracking landed cost calculations as the US statutory effective tariff rate climbed from 3% to over 18% between January and November 2025.

The ECB's econometric analysis yields a tariff pass-through coefficient of 0.95, meaning foreign exporters absorb only 5% of tariff costs. The remaining 95% falls on US firms and consumers. For trade compliance engineering teams building duty calculation engines, this coefficient provides empirical validation for cost allocation models: a 10% tariff increase translates to a 9.5% increase in landed prices, not the full statutory rate.

Key coefficient for landed cost systems: Pass-through of 0.95 means rate caching and duty estimation APIs should assume near-complete cost transmission to importers when projecting total landed costs.

Import volume elasticity data presents a bifurcated picture that affects HTS classification workflows. The aggregate elasticity stands at -3.7, indicating a 10% tariff increase correlates with a 37% decline in import volumes. However, for products that continue trading under tariffs, the elasticity drops to -0.43—a 10% rate increase produces only a 4.3% volume decline. This divergence signals that tariff impacts operate through both extensive margins (products exiting trade entirely) and intensive margins (reduced volumes for products still classified and imported).

Classification system implication: The -3.7 aggregate elasticity suggests significant product categories may require archival or inactive status flags in HTS databases, while the -0.43 coefficient for active trade indicates continued rate accuracy requirements for remaining classifications.

Sector-specific pass-through coefficients diverge significantly from the 0.95 aggregate. The ECB found no statistically significant differences by major trading partner—China, Canada, Mexico, and the EU show similar pass-through behavior—but sector-level variations exist. Automotive trade data reveals structural decoupling: US imports from China and the EU contracted in both unit value and volume, while Canada and Mexico strengthened existing supply chain relationships with surging car import volumes.

The consumer burden currently sits at approximately one-third of total tariff costs, per the ECB's pricing chain analysis. Survey evidence from US firms indicates this share could exceed 50% over the longer term as importers exhaust cost absorption capacity. For compliance systems calculating total cost of goods sold, this progression suggests duty rates require weighting in margin calculations beyond simple ad valorem application.

Engineering teams maintaining tariff rate databases should note the January-November 2025 rate trajectory: a sixfold increase in the effective statutory rate creates significant cache invalidation requirements. Systems pulling HTS rates on extended intervals risk substantial calculation errors given the velocity of 2025 rate changes.

TradeFacts.io tracks these changes nightly. Start a free 30-day trial.