Higher food prices during what has been a historic period of inflation has led to restaurants shrinking the portion sizes on some menu items.

Some consumers have had to make tough choices about how to spend their money, as well.

Economists call the phenomenon "shrinkflation." And according to new data compiled by the reviews website Yelp, diners say it is now rampant.

"In addition to higher prices on grocery stores’ shelves and in restaurants, consumers are also seeing the size or quantity of their goods shrink — a phenomenon that’s also reflected in Yelp," the site says in the report released this week.

Yelp said customers observed "shrinkflation" most commonly at restaurants "serving more affordable offerings like hot dogs, hamburgers, pizza, followed by seafood restaurants, Italian food, and Chinese food."

Yelp declined to provide specific examples from its website of reviews mentioning shrinkflation — but they are increasingly common on Twitter.

Some reviewers are also calling out specific franchises such as Five Guys and Shake Shack. Five Guys did not immediately respond to a request for comment. A spokesperson for Shake Shack said the company has not made any adjustments to its portion sizes.

Prices for meals away from home climbed 7.7% last month, federal data show. Those restaurant prices have now increased for nine consecutive months, and 14 of the last 15 months. In May, Bloomberg reported that fast-casual chains, including Burger King, Domino's and Subway, were all reducing their portion sizes in response to the rising cost of food.

The Yelp data also show consumers booking restaurant reservations further in advance than before, and waiting longer for tables.

“Inflation mentions in Yelp reviews are increasing more than ever before, and for the first time, we’ve seen mentions of shrinkflation-related experiences,” Pria Mudan, Yelp’s data science leader, said in a statement.

Back in the store aisles, numerous consumer packaged goods are also shrinking in size, according to MousePrint.org, a website that tracks retail products.

Food prices in general have increased across the board at rates not seen in decades as the pandemic continues, federal data show. Among the items showing the greatest price hikes are meat, poultry, fish and eggs, where gains have topped 10% on a year-on-year basis every month since September. Those increases have been driven in part by higher fuel and labor costs.

But Mudan said Yelp data also suggest consumers are resilient and adapting in the face of rising prices.