The cost of living in the U.S. dropped in December, led by a slump in commodities that’s roiling global markets.

The consumer-price index declined 0.1 percent after being little changed in November, a Labor Department report showed Wednesday. The median forecast in a Bloomberg survey of economists called for a 0.1 percent increase. Excluding food and fuel, the so-called core index rose 0.1 percent, less than forecast and the smallest gain in four months.

The unabated plunge in energy prices has kept inflation under wraps even as a tighter labor market provides impetus for a pickup in wage growth. Federal Reserve officials are betting prices will accelerate as they consider further increases in the benchmark interest rate.

“The thing that’s been driving everything is energy -- that’s obviously going to weigh on this headline reading,” Jacob Oubina, U.S. economist at RBC Capital Markets LLC in New York, said before the report.

Core consumer prices were projected to rise 0.2 percent according to the median forecast in the Bloomberg survey of economists.

For all of 2015, consumer prices climbed 0.7 percent after rising 0.8 percent in 2014.

Excluding food and energy, they rose 2.1 percent last year following a 1.6 percent increase in 2014.