(The Center Square) – Yet another key inflation marker has hit its highest rate in decades, newly released federal economic data show.

The personal consumer index, a key marker of inflation, rose about half a percent in December, adding to a total 5.8percent  increase in the previous 12 months, according to the Department of Commerce.

That increase is the highest in nearly 40 years.

“The PCE price index for December increased 5.8 percent from one year ago, reflecting increases in both goods and services…” the Bureau of Economic Analysis said. “Energy prices increased 29.9 percent while food prices increased 5.7 percent. Excluding food and energy, the PCE price index for December increased 4.9 percent from one year ago.”

The data comes out as Americans’ pessimism about inflation hits record highs.

Gallup released polling data Wednesday reporting that 79percent  of surveyed Americans “predict inflation will go up," with 50percent  saying it will go up "a lot." According to Gallup, those are the most pessimistic numbers on inflation the group has ever recorded.

Meanwhile, the pollster found Americans are split on economic growth, with 40percent  saying it will increase and 39percent  saying it will decrease.

“In the past, Americans have always been more likely to say inflation will increase rather than decrease, but the current expectation is higher than usual – in fact, it is the highest Gallup has measured in its trend,” Gallup said. “The prior high was 76percent  in September 2005. In recent years, from 2007 through 2020, roughly six in 10 Americans have expected inflation to increase.”

President Joe Biden took fire for the inflation numbers Friday, though defenders point out that wages also rose to help offset the rising costs. Republicans have repeatedly hit Biden and other Democrats on inflation, hoping to carry those issues into the 2022 midterms.

“Every Democratic senator up for election in 2022 has voted with Joe Biden 100percent  of the time,” said Sen. Tom Cotton, R-Ark. “Voting Democratic in 2022 is voting for Biden's record of inflation, crime, and open borders.”