WASHINGTON (AP) — Orders for big-ticket manufactured goods dipped slightly in September as a key category that tracks business investment fell by the largest amount in seven months.

The Commerce Department says orders for durable goods edged down 0.1 percent in September after gains of 0.3 percent in August and 3.6 percent in July. Orders in the category that serves as a proxy for business investment plunged 1.2 percent in September, the biggest setback since a 2.1 percent drop in February.

U.S. manufacturing has struggled this year as American companies have been confronted by a strong dollar which makes U.S. exports more expensive in foreign markets and by the lingering effects from a big drop in oil prices which triggered big investment cutbacks at energy companies.