United States Census Bureau

The Census Bureau is an agency of the U.S. federal government that produces a wide variety of statistical information for the public and private sectors. It has done so since the first federal census of population in 1790, in accordance with the provision in Article I of the Constitution that an “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.” This constitutional requirement has served as the basis for conducting a census of population at 10-year intervals ever since. In response to increased governmental and private sector demands for statistical information, the Census Bureau has become the federal government's largest statistical agency and now produces many statistical series in addition to those derived from decennial censuses.

Regulations governing the collection of statistics by the Census Bureau, formally codified in the U.S. Code, Title 13, Census, require that statistical information remain confidential, meaning that the identity of individuals, households, or organizations that have provided information must not be revealed to any user. Important consequences for the geographic presentation of statistics derive from these regulations, particularly when the capabilities of modern geographic information systems (GIS) are taken into consideration. Data confidentiality safeguards often result in the loss of place-specific geographic detail; nonetheless, statistical information from the Census Bureau provides one of the primary empirical bases for understanding the nation's human geographies, especially with regard to settlement, the characteristics of residents, and a wide range of economic topics.

A variety of geographic requirements are associated with each phase of collecting, processing, and presenting statistics. In the data collection phase, generally referred to as enumeration, one must locate and then obtain information from a person, household, business firm, or other unit of observation at a specific location, usually a street address. In the processing phase, geographic [Page 2910]identifiers are added to responses obtained in the collection phase that will be used to report the tabulated statistics. These requirements have remained essentially unchanged since the first census of 1790, but the manner in which they are operationalized has altered radically since then. The transformation of the nation from 4 million residents situated along the Atlantic Seaboard in 1790 to 305 million residents spread over a continent-scale country of 3.5 million mi.2 (square miles) today has dramatically increased the geographic operational demands. Changing societal demands have brought about increased types of statistical information, with more thematic type-of-area identifiers, for ever more specific locales. Still more dramatic, in terms of their impacts on geographic operations within the Census Bureau, are the technological transformations wrought by modern high-speed computers and the electronic processing of information during the latter 20th and early 21st centuries.

The U.S. Census Bureau began updating its address list of the nation's approximately 130 million housing units in spring 2009. Census workers used confidential and secure GPS-equipped handheld computers to verify, add, and delete addresses. An accurate address list ensures that every household receives a census questionnaire in 2010.

Source: U.S. Census Bureau, Public Information Office (PIO).

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