NEW YORK (CNNMoney.com) -- Manufacturing activity in the Philadelphia area this month reached its lowest level since October 2001, a month after the 9/11 terrorist attacks, according to a report issued Thursday.
The Federal Reserve Bank of Philadelphia's Business Outlook Survey index weakened to -20.9 in January from -1.6 last month, the bank said.
Demand for manufactured goods, indicated by the number of new orders, reached its first negative level in 15 months, the bank said. The number of shipments also declined in the report.
The regional Fed said companies surveyed were less optimistic about manufacturing growth over the next six months than they were in December.
The Philadelphis Fed survey is often seen as a barometer of the U.S. manufacturing industry and a precursor to the national report from the Institute for Supply Management, which will be released Feb. 1.