Powdered formula in U.S. stores dropped to its lowest levels so far this year, with about 30 percent of products out of stock for the week ending July 3. Market-research firm IRI said that while availability improved slightly, shortages remain acute in some states, including Alaska, Utah and Wyoming.

Consumers are also finding fewer choices for brands, sizes or formats of formula on shelves as the variety of available products shrinks. U.S. supermarkets over the four weeks ending on June 26 sold an average of 11 different formula products per store per week – significantly fewer compared to the weekly average of 24 from 2018 to 2021.

Keith Milligan, who controls Piggly Wiggly stores in Georgia and Alabama, said his stores now carry only five of the 30 formula products they typically sell, compared to about 10 in late spring. While shelves aren't empty, they have many gaps as customers purchase only what is available.

The surge in buying formula earlier this year depleted store inventories considerably, said Krishnakumar Davey, president of client engagement at IRI. He said consumers are now working through supplies at home and buying smaller-size containers when they make purchases.

The baby formula shortage was sparked by supply chain problems and the shutdown of a major manufacturing plant. The Wuhan coronavirus (COVID-19) pandemic also caused disruptions in 2020 and last year, with problems tied to shipping, raw materials and packaging.