The economy grew at a moderate or modest pace this summer in eight of the Federal Reserve's 12 U.S. districts, a slowdown from previous reports that may make Fed policymakers more cautious about an interest rate hike.

The Fed's "Beige Book" survey of business conditions found that growth slowed in two districts — Philadelphia and Richmond. The economy was unchanged in New York and Kansas City. In its last report in July, growth was modest or moderate in 11 of 12 districts.

The report comes after Friday's jobs figures showed that hiring slowed in August to half the pace seen in June and July. And a business survey found that manufacturing activity actually shrank last month. Such readings likely darken the outlook for most Fed officials.