(NewsNation) — Rising prices have now hit the fast food industry. Fast food menu prices are up more than 7% between March 2021 and March 2022, according to the National Restaurant Association.

The hike is the largest 12-month increase since 1981. Experts attribute the increased menu prices to higher input costs – particularly food and labor. 

According to the Big Mac Index, the price of the popular McDonald’s burger rose 7% last year. In the past 10 years, the price of the Big Mac jumped 40%.

Studies show the most expensive places to buy a Big Mac are in cities that have a higher minimum wage. For example, the minimum wage in Austin, Texas is $7.25 and the cost of the burger is about $3.75 there. In San Francisco where minimum wage is $16 and the burger costs $5.79. The highest price for the famed burger is in Seattle at about $6.39, where the minimum wage is just over $17.

Experts say the Big Mac price hikes are outpacing inflation and the cost of living in some areas.