After a few minutes of trading, the broad S&P 500 index and the Dow Jones industrial index have both fallen by 0.2 percent. The technology-heavy Nasdaq's composite index by 0.4 percent.
Figures show that the so-called PCE inflation in the USA was 2.6 percent in July, compared to the same period last year. The average forecast among analysts was exactly 2.6 percent.
Compared to June this year, inflation was unchanged.
The PCE inflation is calculated on what is actually consumed, and is seen by the US central bank Federal Reserve (Fed) as the most important price increase measure when decisions on future interest rates are to be made.
President Donald Trump is trying with various means to pressure the Fed to lower the interest rate. The central bank's next interest rate meeting will be held on September 17-18.
The Fed's inflation target is 2 percent.
