WASHINGTON (AP) — U.S. manufacturers saw orders for their products decline in December by the largest amount in five months although the setback for a key category that tracks business investment was not as large as first reported.

Orders to U.S. factories fell 1.5 percent in December, the biggest drop since July, with much of the weakness coming from a plunge in aircraft orders, the Commerce Department reported Tuesday. Orders had risen 1.5 percent in November after a 0.5 percent October decrease.