Wealthier shoppers are opting for Walmart in larger numbers as rising grocery prices affect upper-middle class consumers, according to Business Insider. The trend has boosted the retailer’s earnings, with an 8% growth in annual U.S. sales reported in the last quarter.

The trend was first noticed earlier this year and has persisted into November as the holiday season approaches. Walmart's market-share gains in grocery during August were primarily driven by shoppers in the $100,000 annual income bracket.

"We've continued to gain grocery market share from households across income demographics, with nearly three-quarters of the share gain coming from those exceeding $100,000 in annual income," John David Rainey, Walmart's chief financial officer, told Business Insider.

The big-box retailer, which operates 3,500 grocery locations nationwide, is known for its lower prices and consistent discounts offer. 

"During a period of time when people are more sensitive to price, it makes sense that they would increase the amount of their wallet that would be coming to Walmart because of value," said Walmart CEO Doug McMillon.

Inflation reached its highest rate since 1981 in June, but has slowly begun to decrease. Non-seasonally adjusted food prices rose almost 11% year-on-year in October which, although still high, was lower than the increase in September, according to data from the Bureau of Labor Statistics.