Today I learned

The United States has now hit the worst levels of hunger in decades with 54 million Americans having no reliable access to food.

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New analysis from the Association of American Medical Colleges and USDA shows that 54 million people are food insecure and 23.5 million live in food deserts. This means that 1 in 6 Americans struggles to eat daily. The country is now facing the worst levels of food insecurity since the USDA first started measuring this metric in 1995.

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High food prices also cause food insecurity. If you live in one of America’s many rapidly gentrifying neighborhoods, you may have seen a Whole Foods pop up. While some have playfully rebranded Whole Foods as “Whole Paycheck,” the costs at these types of supermarkets can be ruinous for families that can’t afford to shop there, especially if other more affordable grocery stores get pushed out. This means that a low-income family living in a region of high-priced grocery stores effectively lives in a food desert.

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Groceries sold in food deserts are often far more expensive than those sold in cities or suburban areas. For example, milk prices in food desert tend to be 5% higher and cereal prices 25% higher. This is because getting the food to the regions in the first place can be expensive, leading to higher shelf prices that get passed on to consumers.

https://www.socialpolicylab.org/post/grow-your-blog-community

I don't know where you got your 3% from, but I'm guessing you just made it up without checking.