U.S. manufacturers grew at a faster pace in March, as the pace of employment jumped and new orders and production improved.

The Institute for Supply Management, an association of purchasing managers, said Monday that its manufacturing index rose to 55.3 last month, up from 54.2 in February. Readings above 50 point toward an expansion in manufacturing. The sector has been reporting growth for 31 months.

ISM's survey of companies for the index is a sign that economic growth should continue, even though the global economy, steel tariffs and the trade battle between the United States and China have been sources of concern.

"The primary driver here was employment," said Timothy Fiore, chair of the ISM manufacturing business survey committee. "People are hiring to make sure they have the outputs needed to meet the demand in April, May and June."

The employment component of the index surged 5.2 percentage points, while new orders registered a 1.9-point gain and production notched a 1-point increase.

Out of the 18 sectors surveyed for the report, 16 reported growth, including transportation equipment and primary metals. Only the apparel and paper product sectors reported declines. The food and beverage sector performed the strongest in March.