U.S. consumer prices rose more than expected in January, a further sign inflation is firming after a long run of softness.

The consumer-price index, which measures what Americans pay for everything from salad dressing to fares on public transportation, rose 0.5% in January after rising a seasonally adjusted 0.2% in December, the Labor Department said.

In the 12 months to January, overall prices rose 2.1%, matching the same annual increase as in December.

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