U.S. Census

U.S. Census

The U.S. Census counts every resident in the United States. It is required by the United States Constitution to take place every 10 years.


9 - 12+


Geography, Human Geography, Mathematics, Social Studies, Civics, U.S. History

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The U.S. Census counts every resident in the United States. It is required by the United States Constitution to take place every 10 years. The 2020 census found that there are 331,449,281 people in the U.S.
In order to count and collect information about all those residents, the Census Bureau delivers a 10-question form to every household. This form includes questions about sex, age, race, household relationships, and property ownership. These sets of data are defined as demographic data.
Census-takers are hired to visit households and gather information from residents who have not returned their census form. Census-takers ensure that a community is represented as accurately as possible.
Census data is important on both the national and local level. Population counts help determine the number of seats a state occupies in the U.S. House of Representatives. This process is called apportionment. Every state is entitled to at least one representative in the House, but as a state’s population grows, the state gains representation.
Apportionment can change every 10 years. In 2020, the state of New York lost two representatives because of a declining population. The state of Texas, on the other hand, gained two seats. California, the most populous state, lost one of its 53 representatives in the House, so it now has 52 representatives.
Census data also determines how federal funding is distributed across the country. Federal funding is money provided by the national government for such projects and services as hospitals, schools, bridges, job-training centers, and emergency services. An area with a large number of elderly citizens, for example, may qualify for more funding for hospitals and nursing homes. A densely populated urban area may benefit from increased funding for public transportation.
A wide variety of people and organizations use census data to support research, advocate for causes, and locate specific populations. For example, the Save the Manatee Club petitioned the Florida Fish and Wildlife Conservation Commission to increase its protection of manatees, an endangered species of marine mammal. Using census data, the Save the Manatee Club identified areas with significant construction and development near manatee habitats. The Wildlife Conservation Commission increased its protection of Florida’s at-risk species.
Residents of a suburb of Minneapolis, Minnesota, pushed for further examination of a proposed power plant in the area. Residents were able to use census data to cite the suburb’s larger population of elderly residents and children, groups that are more susceptible to the facility’s environmental impacts. The power plant was not built.
The Census Bureau also conducts specific census programs that collect and present detailed sets of data about the United States, its communities, national economy, and geographic boundaries.

The American Community Survey
The Census Bureau conducts the American Community Survey (ACS). More detailed than the decennial census, the ACS collects and produces population and housing information every year. The ACS does not count the entire population, but instead samples about three million households that represent all counties of the United States and municipios of the U.S. territory of Puerto Rico.
The ACS produces demographic, social, economic, and housing data at one-year intervals for geographic areas with a population of 65,000 or more, at three-year intervals for areas with a population of 20,000 or more, and at five-year intervals for those with less than 20,000.
Data from the American Community Survey is needed to evaluate and manage national, state, and local government programs. Responses to questions about income and housing are used by the U.S. Department of Housing and Urban Development (HUD) to assess the need for housing assistance for elderly, handicapped, and low-income homeowners. Federal programs use age information to target funds and services to children, working-age adults, and the elderly. Local governments use ACS data for budgeting and planning community services programs, such as libraries, schools, and facilities such as swimming pools.
As a whole, the ACS provides up-to-date information that helps all levels of government better understand community issues, accurately target funds for people and projects in need, and measure the performance of programs.

The Economic Census
The Census Bureau also conducts the Economic Census. The Economic Census provides a detailed account of the United States’ economy every five years. This census collects data about economic production, business establishments, agricultural production, and government institutions. It also includes statistics on businesses owned by women and people belonging to ethnic minorities.
Economic Census data is used for a variety of purposes: locating business markets, developing economic policy, evaluating the growth of specific industries, and assisting local businesses.
The Economic Census may show the health care industry is booming, for instance—hiring more doctors, nurses, and other health-care professionals. The manufacturing sector, however, may be slowing. These data influence where the government invests in research and job-training facilities.
The Economic Census assesses the strengths and weaknesses of the U.S. economy and provides data that is used to diversify and strengthen business development throughout the country.

Census Geographic Programs
The Census Bureau works with tribal, state, county, and local officials, as well as agencies such as regional planning commissions, to accurately define the different geographic units used in the U.S. Census and American Community Survey. These units, such as property tracts and neighborhoods, are constantly changing. Census geographic programs ensure that census and survey data reflect those changes.
Each geographic program improves the accuracy of census data through distinct functions. The “Local Update of Census Addresses” program invites tribal, state, and local governments to review and comment on the list of addresses the Census Bureau will use to deliver questionnaires. The “Census New Construction Program” requires tribal and local governments to submit mailing addresses for housing units constructed after the Census Bureau address list was updated.
The “School District Review Program” encourages state officials to provide updates and corrections to the previous year’s school district information. School district information is very important. The number of immigrant students who may need English-language development (ELD) classes, or the number of low-income students who qualify for free meals may change on a yearly basis. English language development and school meal programs are funded by the government.
Ultimately, various census geographic programs help accurately distribute funding offered by federal, state, and local governments.

Census Bureau Newsroom
The U.S. Census Bureau provides news and media agencies with data and special reports. The bureau’s online Newsroom Data Center publishes statistical reports on a variety of topics, including poverty, the foreign-born population, and businesses owned by minorities. The Newsroom aims to communicate census data and its importance in public life with as large of an American audience as possible.

Special Topics
The U.S. Census Bureau also publishes collections of data that are connected to recent events, marking them as “Special Topics.” After the 2010 earthquake in Haiti, the bureau collected data about Haitians living in the United States and Haiti’s own population and demographics. During massive wildfires in Southern California in 2007, the Census Bureau published information about the nation’s growing coastal population to illustrate the importance of emergency planning and preparedness in areas affected by severe weather conditions. These Special Topics aim to increase the public’s awareness and understanding of current events.
The U.S. Census, along with the bureau’s other census programs, requires a considerable amount of time and resources, as well as a large workforce. The end result is large sets of data that tell us about who and what make up our communities, regions, and country as a whole. Ultimately, this data helps people from all walks of life improve the places in which we live, work, and play.

Fast Fact

By the Numbers
Counting the entire population of the United States is no easy task.

  • 360 million questionnaires were printed for the 2010 census. Stacked one on top of another, a pile of these forms would stand about 46.7 kilometers (29 miles) high—more than five times higher than Mount Everest. If stretched end to end, these forms would circle the globe three times!
  • The 2010 questionnaire was available in six languages: English, Spanish, Chinese (Mandarin), Korean, Russian, and Vietnamese
  • 1.2 million people were hired to conduct the 2010 census
  • The 494 local census offices—which manage field work, conduct local recruiting, and visit living quarters—take up about 3.25 million square meters (3.5 million square feet) of office space.

Fast Fact

Everyone Accounted For
The U.S. Census gathers demographic information on everyone living in the United States. This includes citizens, residents who are citizens of another country, long-term visitors, and undocumented immigrants.
The U.S. Census does not calculate the number or demographics of homeless people in the U.S. Instead, it provides a random survey of people staying in homeless shelters or living in designated street locations on a specific date.
Prior to the 1870 census, the program also counted enslaved people. Enslaved people were counted as part of their enslaver's household, further empowering the unjust institution of slavery.

Fast Fact

Population Center
The 2010 census made Plato, Missouri, the new mean center of the U.S. population. The mean center is the point where the nation would balance if every one of its 308.7 million residents weighed the same. The previous population center was 23.4 miles to the northeast in Edgar Springs, Missouri. The mean center is slowly moving southwest.
The population of Plato is 109.

Fast Fact

Right to Privacy
To protect the privacy of U.S. citizens, the Census Bureau does not release specific census data to the public for 72 years. Individual census data from the 1940 census was made public in 2012. Individual census data from the 2010 census will be made public in 2082.

Media Credits

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Diane Boudreau
Melissa McDaniel
Erin Sprout
Andrew Turgeon
Mary Crooks, National Geographic Society
Tim Gunther, Illustrator
Jeannie Evers, Emdash Editing, Emdash Editing
Kara West
Educator Reviewer
Nancy Wynne
National Geographic Society
Last Updated

October 19, 2023

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