Japanese companies paid more for goods and services in 2022 than in any year on record.
Higher costs for raw materials were a major factor driving prices up.
The Bank of Japan says the Producer Price Index for last year rose 9.7 percent from the year before, marking the biggest increase since comparable data became available in 1981.
The rise came after the index climbed 10.2 percent last month from a year earlier.
The increase was mainly driven by higher prices for electricity, gas, steel, petroleum and coal products, as well as food and beverages.
Prices for 88 percent of 515 items surveyed have gone up. The data indicates that companies were passing on the higher costs.
The prices of goods coming into Japan also rose in December.
The Import Price Index climbed 22.8 percent year-on-year in yen terms.
But the pace of increase has slowed since September due to a stronger yen.