The U.S. Department of Agriculture tracks the production and consumption of a long list of agricultural products, reporting on them annually. The most recent USDA report on peanuts shows that on average Americans eat 6.3 pounds of shelled peanuts (or the equivalent in the form of peanut butter or other products containing peanuts) annually, up a half pound from per capita consumption rates a decade earlier.

Geographic reference: United States
Year: 2008
Market size: 2.6 billion lbs.
Source: Food Availablity: Spreadsheets, February 2010 available online here.
Original source: U.S. Department of Agriculture, Economic Research Service