Article 1, Section 2 of the U.S. Constitution states:
"Representatives and direct Taxes shall be apportioned among the several States which may be included within this Union, according to their respective Numbers, which shall be determined by adding to the whole Number of free Persons, including those bound to Service for a Term of Years, and excluding Indians not taxed, three fifths of all other Persons. The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within every subsequent Term of ten Years, in such Manner as they shall by Law direct." --The Constitution of the United States, United States National Archives
Explore over 500,000 data indicators and over 220 years of data for the United States, including all Decennial Censuses, American Community Surveys and many other datasets. The easy-to-use web interface lets users create maps and reports to illustrate, analyze, and understand demography and social change.
County Business Patterns (CBP) is an annual series that provides subnational economic data by industry. This data is useful for studying the economic activity of small areas; analyzing economic changes over time; and as a benchmark for other statistical series, surveys, and databases between economic censuses. Produced as a consistent, annual series since 1964, plus ZIP Code Business Patterns since 1994.