U.S. employers added 136,000 jobs in September — a sign of continued resilience in the labor market amid growing signals that the economy is losing steam.

The unemployment rate fell to 3.5% — the lowest since December 1969 — but the pace of hiring has slowed from last year. The jobless rate was 3.7% in August.

Job gains for the two previous months were revised up by a total of 45,000.

An index of manufacturing activity released on Tuesday showed the factory sector contracting for the second consecutive month. Factories shed 2,000 jobs in September.

The much-larger services side of the economy continued to grow in September but at a significantly slower pace. Private sector employers added 114,000 jobs during the month.