WASHINGTON — U.S. employers added 169,000 jobs in August and many fewer in July than previously thought. Hiring has slowed from the start of the year and could complicate the Federal Reserve’s decision later this month on whether to reduce its bond purchases.

The Labor Department said today the unemployment rate dropped to 7.3 percent, the lowest in nearly five years. But it fell because more Americans stopped looking for work and were no longer counted as unemployed. The proportion of Americans working or looking for work fell to its lowest level in 35 years.

July’s job gains were just 104,000, the fewest in more than a year and down from the previous estimate of 162,000. June’s figure was revised to 172,000, from 188,000.

The revisions lowered total job gains over those two months by 74,000.

Employers have added an average of just 148,000 jobs in the past three months, well below the 12-month average of 184,000.

Dow Jones industrial average futures rose modestly after the report was released. The yield on the 10-year Treasury note fell to 2.87 percent, from 2.95 percent, in the first few minutes after the jobs figure was released. Investors may view the weaker jobs picture as a sign that the Fed could hold off on slowing its bond buying when it meets on Sept. 17-18.

The report “is a mixed bag that can be used to support an immediate tapering of the Fed’s monthly asset purchases or delaying that move until later this year,” Paul Ashworth, an economist at Capital Economics, said. However, Ashworth said he still expects the Fed to begin tapering next month.