Chart of the Week: Inbound Ocean TEU Volume Index – USA SONAR: IOTI.USA
Import container bookings, as measured by the Import Ocean TEUs Index (IOTI), have rebounded sharply after plunging in response to the historic tariffs imposed on Chinese goods in April. This swift recovery has raised questions about the potential impact on supply chains and surface transportation as a new wave of imports makes its way to U.S. ports.
The IOTI, a 14-day moving average of twenty-foot containers departing from global ports to the U.S., dropped from near-pandemic-era highs in early April to holiday-period lows by mid-May.
The threat of tariffs prompted companies to preemptively order goods and stockpile inventory to avoid cost-prohibitive levies—tariffs that would have significantly reduced, if not eliminated, demand, particularly for goods from China, their primary target.
China accounts for the largest share of U.S.-bound container imports, typically around 40%. Vietnam has been a distant second post-pandemic, representing roughly 8%. Note that these figures reflect container volumes, not trade dollar values.
China’s share of bookings fell to 30% on May 18, down from 41% on April 1. Increased orders from countries like Vietnam and India helped fill the gap, but only offset about 10% of the lost volume. Now, China’s share has rebounded to over 40%, and the IOTI is back to its level from the same period last year.
This rebound indicates that import volumes could rise at U.S. ports in the coming weeks. However, the extent of inland freight movement will depend largely on inventory levels, many of which were already elevated in anticipation of the tariffs.
So far, only international intermodal rail volumes have shown a significant loss directly tied to imports decline. Volumes of international containers (ORAILINTL) dropped roughly 8% from April to May, while domestic container traffic (ORAILDOML) and truckload tender volumes (OTVI) remained relatively flat.
For inland freight demand to surge, inventory levels in interior markets will need to show meaningful reductions. Additionally, seasonal goods that could not be ordered early may contribute to the next wave of freight activity.
The current transportation environment remains vulnerable to disruption. While it has generally met demand over recent years, reduced capacity and weakened carrier resilience have left it more exposed. Carriers are now rejecting load requests at their highest rate since 2022. Though rejection rates remain modest, their volatility and upward trend are notable. A surge in demand concentrated on one side of the country could quickly tighten capacity.