Consumer prices in May had their biggest increase since 2013 as gasoline costs jumped sharply after months of declines, the Labor Department said Thursday.
The consumer price index, which covers a variety of goods and services, rose 0.4% compared with a 0.1% increase the previous month.
May was the fourth straight month that the index rose after three straight monthly declines caused by lower oil prices.
But a reversal in gas prices has increased inflationary pressure. The gas price index rose 10.4% in May after declining 1.7% the previous month.
The increase in gas prices was the main factor in the overall rise of the consumer price index, a closely watched measure of inflation.
Taking out volatile energy and food prices, so-called core prices rose 0.1%, the smallest increase since December. Food prices were unchanged in May for the second straight month.
A steep decline in oil prices that began last year has pushed inflation extremely low. Despite the rise in May, gas prices were down 25% from a year earlier.
For the 12 months ended May 31, overall consumer prices were unchanged, the Labor Department said. Still, that's an improvement over the 0.2% annual decline through April.
Federal Reserve policymakers are watching inflation as they decide when to raise a key short-term interest rate for the first time since 2006. The Fed wants about 2% annual inflation.
The Fed uses a different annual inflation measure, based on personal consumption expenditures, that was up 0.1% in April, the latest data available.
Excluding food and energy, core consumer prices were up 1.7% in the 12 months ended May 31. The figure was down from 1.8% in April.
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