The Supermarket Panel collects data annually from individual supermarkets on store characteristics, operations, and performance. It was established in 1998 by the Food Industry Center as the basis for ongoing study of the supermarket industry. The Panel is unique because the unit of analysis is the individual store and the same stores are tracked over time. This makes it possible to analyze the processes by which new technologies, business practices, and competitive forces are changing the industry. The 2001 Supermarket Panel consists of 563 stores selected at random from the nearly 32,000 supermarkets in the U.S. or invited to participate through their affiliation with IGA. These 563 stores are located in forty-seven states and the District of Columbia. They are a representative cross section of the industry, including stores from all formats that belong to ownership groups ranging from single stores to the country's largest chains.