WASHINGTON — Retail sales grew in June after dipping month to month in May, in a sign that the industry is benefiting from an improving economy.

Retail sales rose 0.6% in June, according to the U.S. Commerce Department, which also revised data for May to show sales falling 1.7% instead of declining 1.3% as previously reported.

Many economists had expected retail sales to fall again in June as consumers took advantage of a reopening economy to spend more on services.

The National Retail Federation’s calculation of retail sales — which excludes automobile dealers, gasoline stations and restaurants to focus on core retail — showed that June sales were up 0.8% seasonally adjusted from May and up 12.1% unadjusted year over year. That compared with a month-over-month decline of 1.9% and a year-over-year increase of 16.5% in May. NRF’s numbers were up 19.3% unadjusted year over year on a three-month moving average.

“Continued growth in June retail sales shows enduring strength in the American consumer,” NRF president and chief executive officer Matthew Shay said. “Heading into the back-to-school season, we expect record sales as families purchase electronics, shoes and backpacks for in-person learning this year. However, as the drop in monthly auto sales indicates, retailers are facing product shortages and supply chain constraints. We urge Congress and the administration to enact meaningful, bipartisan infrastructure legislation that is critical for retailers who depend on a safe, reliable and efficient transportation system to drive further economic growth.”

June sales saw a boost from the annual Amazon Prime Day promotion and the competing deals offered by many other big retailers. Record-high temperatures in some parts of the country and tropical storms in others may have affected sales, and methodology the Census Bureau uses to adjust results for seasonal variations may have affected the numbers reported by the agency.

For the first six months of the year, sales were up 16.4% over the same period in 2020. With the rate of growth expected to slow in the second half of the year, that is consistent with NRF’s revised forecast that 2021 retail sales should grow between 10.5% and 13.5% over 2020 levels.

“We’re continuing to see an impressive recovery,” NRF chief economist Jack Kleinhenz said. “The economy and consumption are particularly sensitive to government policy, and the boost we saw from government support earlier in the year is continuing to show benefits. Reopening of both stores and the overall economy has progressed, and even higher prices seen in some retail categories reflecting the push-and-pull of supply chain challenges haven’t proven to be a deterrent to spending. As more people get vaccinated and get out, some of the growth will shift to services rather than retail, but there’s enough momentum to support both.”