Stock market news live updates: Stocks rise as investors eye inflation data showing biggest jump since 1982

Stocks rose Wednesday as investors eyed a new report on inflation, which showed another decades-high rate of price increases across the recovering economy. Still, this came a day following remarks from Federal Reserve Chair Jerome Powell reasserting that the central bank would step in as needed to rein in rising prices.

The Bureau of Labor Statistics' December Consumer Price Index (CPI) showed prices rose at a 7.0% year-over-year rate at the end of 2021, marking the fastest increase since 1982. This matched consensus estimates, based on Bloomberg data, and accelerated from November's already elevated 6.8% increase. On a month-over-month basis, consumer prices rose 0.5%, or slightly more than the 0.4% rise expected, to mark an eighteenth consecutive month of price increases.

Excluding food and energy prices, the so-called core measure of consumer prices rose 5.5% in December over last year, coming in at the fastest rate since 1991.

Wednesday's market moves came following a rebound rally on Tuesday, with markets at least temporarily finding relief in assurances from Federal Reserve Chair Jerome Powell that the central bank would step in as necessary to ease rising prices. In Powell's renomination hearing before the Senate Banking Committee, the central bank leader reiterated that the Fed would use its policy tools to bring down inflation.

“If we see inflation persisting at high levels, longer than expected, if we have to raise interest rates more over time, then we will,” Powell said during the hearing.

The central bank previously telegraphed it was eyeing three interest rate hikes this year to bring benchmark rates up from their current near-zero levels. However, some top Wall Street firms have predicted the Fed will raise rates four times given the current inflationary backdrop.

But though Powell doubled down on the Fed's goal of curbing inflation and using interest rate hikes as a tool to achieve this, he revealed little further about the Fed's plan to begin shrinking its nearly $9 trillion balance sheet. The Fed's December meeting minutes last week suggested central bank officials were beginning to discuss drawing down the Fed's balance sheet after nearly two years of asset purchases to help support markets during the pandemic. Powell did reiterate in his hearing he expected the balance sheet runoff process would begin this year.

"I think the biggest comment on most investors' minds that we talk to around the world would be a 'policy mistake' that the Fed might be too aggressive," Brian Belski, BMO Capital Markets chief investment strategist, told Yahoo Finance Live on Tuesday. "Mr. Powell basically came out today and said this is going to be a process ... with respect to how long this is going to take, and I think that's what's calming investors."