The United States Census Bureau is one of the world's largest producers of social and economic data and statistics. Looking through Census statistics can be a thought provoking research activity, but there is specialized language to learn. This guide is intended to provide anyone new to census statistics and data with a brief overview of the terminology, concepts and sources of Census information the bureau and others provide. If you run into issues finding the Census information you need, contact the Library for help.
Simply put, a "census" is an official count of everyone in a geographic area. The United States Census Bureau has been conducting a census of the country's population every 10 years since 1790. The Census is the primary source of demographic information (population, household size, income, business ownership, etc) for the United States government and the statistics gathered can support academic research in virtually all disciplines, from Political Science, History, Business, Ethnic Studies to Environmental Studies and beyond. While the actual Census has changed over time, the richness of the data has not.
The main reason the U.S. conducts a census lies in our representative government and is spelled out in the country's founding document. Article 1, Section 2 of the U.S. Constitution is about the make-up of the House of Representatives and apportionment, but clause 3 directs an enumeration of the population, aka a census, to be taken every ten years:
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.
Census statistics of the voting age population prescribe how congressional seats are apportioned in the House of Representatives. These statistics also help the federal government allocate funds though various spending programs. Here is what President Barack Obama said about the 2010 Census:
In addition to its governmental uses, Census data and statistics are usually the authoritative source used by many non-governmental granting agencies and foundations in evaluating grant applications. Census statistics can also be used in research projects ranging from academic papers a couple pages in length to a presentation, to a full-lenghth book.