Business inventories rose 0.7% in May, the Commerce Department said Wednesday.
The increase in goods unsold at factories, retailers and wholesalers followed a 0.4% increase in April.
Sales rose 1.7%, the most since November.
The inventory gain was higher than analysts’ forecasts of a 0.5% increase, Bloomberg reported.
When sales are growing, it usually means trucking is seeing additional demand to deliver goods and restock shelves.
Higher inventories mean goods are not being sold at a rapid pace, which could lower demand for trucking services.