Orders for big-ticket US manufactured goods declined for the first time in five months in September, largely due to falling orders for planes and cars, according to government data released Wednesday.

Durable goods orders last month fell by 0.4 percent, seasonally adjusted, from August, the Commerce Department reported, but the September decrease was less severe than analysts forecast.

A 2.3 percent drop in transportation orders drove the decline, according to the data, with non-defense aircraft orders, such as Boeing's jets, decreasing 27.9 percent in the month.

However, if the transportation sector is excluded, overall orders climbed 0.4 percent, which Oren Klachkin of Oxford Economics called "a sign that many businesses stayed optimistic on the economic outlook even as the Delta variant continued to spread across the country."

The effects of the global semiconductor shortage could be seen in the data, with motor vehicle and parts orders dropping 2.9 percent as automakers continue to struggle to keep assembly lines going amid a shortage of the crucial computer chips.

A fall in orders in the transportation sector, such as Boeing's aircraft, dragged overall US durable goods demand lower in September
A fall in orders in the transportation sector, such as Boeing's aircraft, dragged overall US durable goods demand lower in September GETTY IMAGES NORTH AMERICA / David Ryder

The overall decrease would have been worse if not for the defense sector, where orders for aircraft and parts surged 104.3 percent, and capital goods rose 28.4 percent.

Excluding defense, overall orders would have decreased two percent, the Commerce Department said.

Rubeela Farooqi of High Frequency Economics predicted demand would continue to support the manufacturing sector even as the global supply chain bottlenecks create challenges in the months ahead.

"The trend in orders is likely to remain positive given inventories remain lean. But for the manufacturing sector, supply bottlenecks and shortages are key constraints that are likely to persist in the near term," she said in an analysis.