It can be difficult to find consumer information (for example, which age group purchases the most yogurt?), and the databases below are your best bets.
The U.S. government collects the most comprehensive data about the American people (all households are surveyed every 10 years for the Census, and a sampling is taken every 5 years for the American Community Survey). Most government information is available for free, but CU pays for some of the resources below that have enhanced features.
2000 Decennial Census. By U.S. Government. Public Domain.