NEW YORK -- The largest retail trade group in the United States said Tuesday it expects consumers to spend more during the upcoming holiday shopping season but the growth in sales to be slower than last year because of concerns over persistent inflation and prices.

The National Retail Federation said its 2024 forecast indicates shoppers will make $979.5 billion to $989 billion worth of purchases in November and December, which would represent a 2.5%-3.5% increase over the same two-month period a year ago.

However, the $955.6 billion spent during the 2023 holiday shopping season was 3.9% more than in 2022.

This year's predicted pace is consistent with the average increase of 3.6% from 2010 to 2019. During the coronavirus pandemic, Americans ramped up their spending. Holiday season sales rose 9% in 2020 from the year before, and they soared 12.4% in 2021, according to the National Retail Federation.

The trade group makes its calculations based on government figures. The numbers exclude sales at automobile dealers, gasoline stations and restaurants.

The forecast considers economic indicators such as employment, wages, consumer confidence, disposable income, consumer credit, previous retail sales and weather.

"Interest rates are still a little higher than they were in recent memory," National Retail Federation CEO and President Matt Shay said. "Consumers do have those interest rates and the lingering inflation on their minds. So we expect that consumers will continue to be more price-conscious and pragmatic in their spending decisions."

The retail federation issued its look-ahead as the data shows U.S. consumers continuing to spend, powered by sturdy hiring, low unemployment and healthy household finances. Moreover, gas prices are coming down, leaving a little extra money for shoppers to spend on gifts.

But there are plenty of challenges this season, including a presidential election that could create a big distraction from shopping in November. NRF officials said it was nearly impossible to measure the election's impact on spending.

With Thanksgiving falling on Nov. 28, there also will be six fewer days between the holiday and Christmas Day compared to last year. Other factors that could hurt holiday sales: the economic impact of hurricanes Helene and Milton, NRF officials said.

Walmart, the nation's largest retailer, plans to advertise savings on Thanksgiving meal products starting Oct. 14, about two weeks earlier than last year.