Pie chart with 3 items.

Traditional foodstore sales by segment, 2011
Retail food and nonfood sales were $571 billion in 2011

Item 1, Grocery stores, including supermarkets 91.1%.
Item 2, Convenience stores 5.5%.
Item 3, Specialized stores 3.4%.

Source: U.S. Census Bureau, Annual Retail Trade Report, 2011.