WASHINGTON—New orders for U.S.-made goods unexpectedly rose in September, though manufacturing remains constrained by input shortages. The Commerce Department said on Wednesday that factory orders increased 0.2 percent in September. Data for August was revised down to show orders rising 1.0 percent instead of 1.2 percent as previously reported. Economists polled by Reuters had forecast factory orders unchanged. Orders gained 17.6 percent on a year-on-year basis. Manufacturing, which accounts for 12 percent of the economy, is being driven by still-strong demand for goods despite spending shifting back to services. Businesses are rebuilding depleted inventories, but shortages of labor and raw materials stemming from the COVID-19 pandemic remain challenges. The widespread shortages restrained economic growth to its slowest pace in more than a year in the third quarter. An Institute for Supply Management survey on Monday showed manufacturing activity slowed in October, with all industries reporting record-long lead times for raw …