U.S. consumers are in the midst of one of the longest stretches of elevated inflation of the past century. Some are beginning to act like it's a new normal, raising alarm bells for members of the Federal Reserve.

Wednesday's consumer price index release showed a 3.7% increase year over year in September. CPI has nowed around 65 months — that's more than five years — of consecutive annual readings above 2%, a widely accepted target for inflation in the U.S.

This yearslong spell of high inflation has cast a dark cloud over everyday Americans' view of the economy, and could shape everything from how they budget to how they vote in next month's midterm elections. At the Fed, leaders are left questioning whether consumers' inflationary expectations are becoming too entrenched to rein in.

"They're starting to accept high inflation as just a fact of life," Cleveland Fed President Beth Hammack wrote in a social media post last week. "That's concerning."

Inflation by the numbers The current streak of stubborn inflation ranks among the most persistent in modern U.S. history.

The uninterrupted string of above-2% monthly CPI readings is the longest of the 21st century, according to a CNBC analysis of data from the Bureau of Labor Statistics. The U.S. has seen longer periods on only two other occasions going back to the late 1940s.

Since inflation started running above 2% in early 2021, the average CPI reading has sat around 4.5%. The last time a streak had a mean reading that high was during a period ending in the 1980s.

Consumers are expecting inflation to accelerate. The one-year inflation outlook in September rose three-tenths of a percentage point to 3.9%, its highest reading in more than three years, according to the New York Fed's Survey of Consumer Expectations released last week. How consumers respond One of the main worries of central bankers is that businesses and consumers may start permanently adjusting their behaviors to account for high prices. That can have ripple effects through the economy.

Businesses anticipating rising costs can preemptively hike prices for consumers. Workers expecting sticky inflation will ask for steeper pay raises to get ahead of any sticker shock.

All of this can make inflation a self-fulfilling prophecy, rendering the monetary policy tools at the Fed's disposal less effective in slowing price growth.

"Inflation expectations have to be anchored for monetary policy to affect the economy in an effective and predictable manner," said Gary Richardson, an economist and former historian at the Fed. "That's got to be number-one goal of any central bank." At this juncture, Fed officials are closely watching to see if and how consumers respond to inflationary pressures.

During an event last month, Minneapolis Fed President Neel Kashkari said he heard from a labor union leader that inflation was "worse" than a recession for their members. Kashkari said that conversation influenced how he views the trade-off within the Fed's so-called dual mandate, which calls for stability in prices and maximum employment.

At a gathering of economists in Ohio this week, Hammack told the audience that she did not take the fact that long-run inflation expectations have stayed anchored "for granted." With each month that inflation comes in high, she warned that the risk grows of an "inflationary mindset" getting entrenched.

Economists widely view interest rate hikes as the Fed's main mechanism for slowing demand and, in turn, putting downward pressure on the annual pace of price growth. After hiking interest rates in September, Fed funds futures traders anticipate the central bank will raise borrowing costs further in December and in 2027.

In the long run, Diane Swonk, chief economist at consultancy KPMG, said interest rate hikes can benefit consumers by getting inflation under control. But in the near term, Swonk said consumers can feel more pressure due to higher borrowing costs.

"Inflation is like a cancer, and if you let it metastasize and go further, it's even worse," Swonk said. "Even when the cure hurts, it's better than letting it metastasize." Unhappy shoppers In Hammack's district, the Cleveland Fed chief said via social media that she's found evidence that residents are "choosing" rather than "trading down." For instance, she said they need to pick whether to pay for groceries or essential bills.

Consumers have lamented the cumulative price increases they now see in everyday life after the years-long run of high inflation. Adding to their woes is the fact that year-over-year inflation has run at a faster clip than wage growth in recent months, meaning the average consumer has lost purchasing power.

The University of Michigan's closely followed consumer sentiment survey earlier this year fell to the lowest levels ever seen. The highest share of respondents citing high prices as a reason for having worse personal finances surpassed 50% for the first time on record in 2026.

High prices are "dominating consumer thinking," said Joanne Hsu, the director of Michigan's survey. "They still consider it an unacceptable fact of life." Compared with Democrats, consumer sentiment has tumbled more sharply among Republicans and independents this year. The question now is if voters angered about the rising cost of living will shift control in Washington away from Republicans and President Donald Trump in the midterm election.

Despite those glum outlooks, economists say that everyday Americans shouldn't bank on prices coming down from current levels. Deflation — which is when annual price growth falls below 0% — could put the national economy on a downward spiral.

Instead, their hope should be that inflation's 12-month growth rate can cool to levels below the pace of pay increases. If that happens for a long enough period, the higher wages and increased purchasing power would leave shoppers better equipped for today's prices.

Olena Nicks, an analyst and local lawmaker in Long Island, New York, is one of those consumers tightening the purse strings in the face of lofty prices. Nicks said she's specifically noticed steep price increases over recent years in the grocery store produce aisle and when looking at airline flights for vacations.

In response, the 34-year-old said she's cut back on purchasing meals at restaurants or from fast-food chains. Her friend group has forgone leisure activities like bowling, opting instead for less-costly nights spent in someone's home. "Frustrated is an understatement," Nicks said. "It feels like you're stuck."