President Joe Biden and Democratic lawmakers are making a push to raise the federal minimum wage to $15 an hour from the current $7.25. Some lawmakers and business owners who are against the idea say it would create harmful effects, including business closures, job loss, and an acceleration of the shift toward automation.

But those effects didn’t materialize in a five-year analysis of the impacts of minimum wage increases at state and local levels at more than 10,000 McDonald’s MCD, -0.65% fast-food restaurant locations in the U.S.

In fact, as a result of the nearly 300 minimum wage increases that took place between 2016 and 2020, many McDonald’s restaurants paid workers slightly above the new minimum wage to retain employees. That’s according to new research by Orley Ashenfelter, a Princeton University economist, and Stepan Jurajda, an economist at Charles University in Prague.

The two economists collected survey data on the price of a Big Mac (including sales tax) and wage rates of basic hourly workers above the age of 18 from at least 90% of U.S. counties with a McDonald’s in every year.

They found that the higher cost of labor that results from increasing minimum wages gets passed on to consumers in the form of more expensive Big Macs.

More specifically, they estimated that a 10% minimum wage increase leads to a 1.4% increase in the price of a Big Mac. On average, Big Macs cost $5.66 in the U.S., according to The Economist’s Big Mac Index.