The jump from the previous December was the largest year-on-year increase for any month since the Federal Statistics Office began compiling the producer price numbers in 1949, the office said.
December's figures marked the third consecutive month of very high numbers after October and November showed increases of 18.4% and 19.2% respectively.
The average expectation among analysts polled by Reuters was an annual increase of 19.4%.
Producer prices also registered a record jump of 5% month on month, against 0.8% in November.
Energy prices were up 69% compared with December 2020, the Federal Statistics Office said. Stripping out energy prices, producer prices rose 10.4% on the year.
Producer prices are considered a leading indicator for inflation. They are recorded at the factory gate - before products are processed further or go on sale - and can provide an early indication of consumer price trends.
(Reporting by Miranda Murray; Editing by Zuzanna Szymanska and David Goodman)
