U.S. wholesale inventories increased slightly more than initially thought in April as growth in sales moderated, data showed on Wednesday.

The Commerce Department said that wholesale inventories advanced 2.2%, instead of 2.1% as reported last month. Data for March was revised higher to show stocks at wholesalers rising 2.7% instead of the previously reported 2.3%.

Economists polled by Reuters had expected April inventories would be unrevised. Wholesale inventories increased 24.0% in April on a year-on-year basis. Inventories are a key part of gross domestic product.

Wholesale motor vehicle inventories rose 1.3% after accelerating 2.4% in March. Wholesale inventories, excluding autos, increased a solid 2.2% in April. This component goes into the calculation of GDP and suggested that inventory investment could provide a lift to economic growth this quarter.

A record trade deficit and slower rate of inventory accumulation relative to the fourth quarter's brisk pace weighed in output, resulting in GDP dropping at a 1.5% annualized rate in the January-March quarter. Growth estimates for the second quarter are as high as a 4.8% rate. Sales at wholesalers gained 0.7% in April after increasing 1.8% in March. At April's sales pace it would take wholesalers 1.25 months to clear shelves, up from 1.23 months in March.