An index of wholesale prices rose 9.6% compared to a year ago, its largest annual gain since the government began calculating in 2010.
The big picture: The Producer Price Index (PPI) started off the year showing 12-month price growth of 1.6% and has moved up steadily all year.
Why it matters: The PPI is a key leading indicator for the prices that consumers eventually pay.
"[December] should be the peak," wrote Pantheon Macroeconomics in a research note. "A combination of favorable base effects and smaller month-to-month increases should start to drive down the year-over-year rate."
State of play: On the whole, companies passed on enough of their input cost increases to customers during Q3 to preserve profit margins.
Watch for whether margins continue to hold up in Q4. The first round of earnings start rolling in next month.