U.S. manufacturers' and trade inventories rose 0.4 percent in April from the previous month, providing a hint of the ongoing economic recovery, the Department of Commerce reported Wednesday.

The April inventory figure of 1.575 trillion U.S. dollars also represented a 6.0 percent increase from a year earlier, said the department.

The total business inventories-to-sales ratio, which measures the time span of the inventories being sold, stood at 1.26 by the end of April, slightly higher than the 1.25 level one year earlier.

In addition, combined sales by manufacturers, wholesalers and retailers gained 0.2 percent from March to 1.25 trillion dollars in April, said the department.

It is normally interpreted as a positive sign of economy when businesses step up stockpiles. Companies need to order more goods to build their inventories, which generally will boost factory production.