WASHINGTON — An inflation gauge that is closely monitored by the Federal Reserve showed price increases remained elevated in September amid brisk consumer spending and strong economic growth.

Friday’s report from the Commerce Department showed that prices rose 0.4 percent between August and September, the same as the previous month. And, compared with 12 months earlier, inflation was unchanged at 3.4 percent.

Taken as a whole, the figures the government issued Friday show a resilient consumer, willing to spend briskly enough to power the economy even in the face of persistent inflation and high interest rates. Spread across the economy, the strength of that spending is itself helping to fuel inflation.

In a cautionary note, consumers relied increasingly on savings to fuel their shopping last month. Income growth slowed. Adjusted for inflation, income actually fell slightly.

Yet spending jumped 0.4 percent after adjusting for inflation. The saving rate fell to 3.4 percent, down from the 6-percent-plus average before the pandemic.

“That is clearly unsustainable, and we expect spending growth will slow sharply in the quarters ahead,” said a lead U.S. economist at the consulting firm Oxford Economics, Michael Pearce.

September’s month-to-month price increase exceeds a pace consistent with the Fed’s 2 percent annual inflation target, and it compounds already higher costs for such necessities as rent, food, and gas.

The Fed is widely expected to keep its key short-term interest rate unchanged when it meets next week. Yet its policymakers have flagged the risk that stronger growth could keep inflation persistently high and require further rate hikes to quell it.

Since March 2022, the central bank has raised its key rate to roughly 5.4 percent from near zero in a concerted drive to tame inflation. Annual inflation, as measured by the separate and more widely followed consumer price index, has tumbled from the 9.1 percent peak it reached in June of last year.

On Thursday, the government reported that strong consumer spending drove the economy to a robust 4.9 percent annual growth rate in the July-September quarter, the best such showing in nearly two years. Heavy spending by consumers typically leads businesses to charge higher prices. In Friday’s report on inflation, the government also said that consumer spending last month jumped a robust 0.7 percent.

Spending on services jumped, Friday’s report said, led by greater outlays for international travel, housing, and utilities.

Excluding volatile food and energy costs, “core” prices rose 0.3 percent between August and September, above the 0.1 percent uptick the previous month. Compared with a year earlier, though, core inflation eased to 3.7 percent, the slowest rise since May 2021 and down from 3.8 percent in August.

A key reason why the Fed may keep rates unchanged through year’s end is that September’s 3.7 percent year-over-year rise in core inflation matches the central bank’s forecast for this quarter.

With core prices already at that level, Fed officials will likely believe they can “proceed carefully,” as chairman Jerome Powell has said they will do, and monitor how the economy evolves in coming months.

Still, the data in Friday’s report showed that while prices for many goods, including cars, furniture, and appliances, are actually falling, the price increases for services remain chronically high.

Restaurant meals, for example, rose 0.4 percent in price betwee August and September, up from a 0.2 percent rise the previous month. They are now 5.8 percent more expensive than they were a year earlier.

One measure the Fed is monitoring closely — services prices, excluding energy and housing — jumped 0.4 percent last month, after rising only 0.1 percent in August. The Fed watches that gauge because it tracks prices in a set of industries that are labor-intensive and particularly sensitive to rising wages. Higher wages can fuel inflation if businesses pass on their higher labor costs by raising prices.

A solid job market has helped fuel consumer spending, with wages and salaries having outpaced inflation for most of this year. Yet Friday’s report showed that the growth in overall income — a category that, in addition to wages, includes interest income and government payments — has slowed.

Adjusted for inflation, after-tax income slipped 0.1 percent in September, the third straight monthly decline. Shrinking incomes could weaken spending and growth in the months ahead.

Associated Press