China container ship data shows the tariff-driven export rush

Donald Trump has driven a rush at China's container ports.

With exporters keen to get ahead of announced US tariffs and potential future escalation, weekly shipping figures are showing that container throughput in 2025 has been significantly above the 2024 trend. Traffic especially picked up in April, when the US president announced his "Liberation Day" tariffs. (At the time of publication, the US and China had agreed to significantly reduce tariffs imposed just weeks before on each other's goods.)

We've charted several other measures of China-US trade, viewed through the lens of high-frequency Marine Traffic shipping data.

Container ship departures from 21 major Chinese ports saw a remarkable surge from February to April; similarly, we can see that container-ship arrivals at the biggest US ports are also above trend for the year as a whole, though this has slowed since March.

Another measure of trans-Pacific traffic is congestion at US container ports. We've compared 2022 to 2025; at the start of this year, the surge in traffic posed a short-term logistical challenge. There was a sharp increase in the number of vessels waiting for a place to dock and unload. (To be sure, this paled in comparison to the post-pandemic supply-chain disruptions; the 2022 backlog of vessels has never been equaled.)

Our final two charts illustrate how high-frequency shipping data can get CEIC users an early sense of official trade data. We've charted the number of vessels leaving Chinese ports against official export data, and the number of arrivals at American ports against official import figures. There is a strong correlation in both cases.