The increased cost of a burger starts with the all-essential bun. The price of bread went up 7.1 percent in March compared to a year prior, while the price of all bakery products climbed 9.1 percent.

U.S. port congestion has hampered a broad swath of American businesses over the past two years and the nation’s bread bakers are no exception.

The U.S. imports most of its gluten from overseas nowadays, along with product packaging and specialty ingredients, said Robb MacKie, the president and CEO of the American Bakers Association. The port backlog meant bakers were waiting longer for those products, assuming they could get them at all.

MacKie said about 50 input costs that bakers track had jumped by double digits as of January, including hikes in the prices for wheat and the natural gas needed to power ovens. And that was before Russia invaded Ukraine, a major wheat exporter.