Prices rose 8.2 percent compared with a year earlier, the latest Consumer Price Index showed on Tuesday, evidence that the price stability sought by the Federal Reserve remains an elusive and distant destination.

Compared with August, prices were up 0.4 percent, the Department of Labor’s Bureau of Labor Statistics said.

Core CPI, which strips out volatile food and energy prices, rose 6.6 percent compared with a year ago. That is the highest rate of core inflation since 1982, surpassing the recent 6.4 percent highs hit in February and March. For the month, core prices were up 0.6 percent.

Economists had expected the index to be up 0.2 percent on a monthly basis and 8.1 percent compared with a year ago. Core CPI was forecast as rising 0.4 percent month-to-month and 6.5 percent compared to a year ago.

The monthly figures show inflation is accelerating. After falling to zero in July, the headline consumer price index has risen for two straight months. In August it was rising at a 0.12 percent rate. Core prices were up 0.31 percent in July and 0.56 percent in August.