New orders for key U.S.-made capital goods increased more than expected in September and shipments rose for an eighth straight month, suggesting business spending on equipment remained robust in the third quarter.

The Commerce Department said on Wednesday non-defense capital goods orders excluding aircraft, a closely watched proxy for business spending plans, rose 1.3 percent last month after an upwardly revised 1.3 percent increase in August.

Economists polled by Reuters had forecast orders of these so-called core capital goods increasing 0.5 percent last month after a previously reported 1.1 percent jump in August. Core capital goods orders advanced 3.8 percent year-on-year.

Shipments of core capital goods climbed 0.7 percent after soaring 1.2 percent in August. Core capital goods shipments are used to calculate equipment spending in the government's gross domestic product measurement.

The Commerce Department said it was unable to isolate the effects of Hurricanes Harvey and Irma on the data as the survey is "designed to estimate the month-to-month change in manufacturing activity at the national level and not at specific geographic areas."