View source for United States census

{{Short description|Decennial census mandated by the US Constitution}}
{{Use American English|date = March 2019}}
{{Use mdy dates|date = March 2019}}
{{Infobox recurring event
| name         = United States census
| native_name  =
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| logo         = Seal of the United States Census Bureau.svg
| logo_size    = 250px
| logo_alt     =
| logo_caption = The [[United States Census Bureau|Bureau of the Census]] is part of the [[United States Department of Commerce]].
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| status       = <!-- e.g. defunct, active, inactive ... -->
| genre        = <!-- e.g. natural phenomena, fairs, festivals, conferences, exhibitions ... -->
| date         = <!-- {{start date|YYYY|mm|dd}} "dates=" also works, but do not use both -->
| begins       = <!-- {{start date|YYYY|mm|dd}} -->
| ends         = <!-- {{end date|YYYY|mm|dd}} -->
| frequency    = Decennial
| venue        =
| location     = 4600 Silver Hill Rd.<br /> [[Suitland, Maryland]] 20746
| coordinates  = <!-- {{coord|LAT|LON|type:event|display=inline,title}} -->
| country      = United States
| years_active = <!-- {{age|YYYY|mm|dd}} Date of the first occurrence -->
| first        = {{start date and age|1790|8|2}}
| founder_name = <!-- or | founders = -->
| last         = {{End date and age|2020|4|1}}
| prev         =
| next         = {{start date and age|2030|4|1}}
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| website      = {{URL|https://www.census.gov/}}
| footnotes    =
}}
The '''United States census''' (plural censuses or census) is a decennial [[census]] that is legally mandated by the [[Constitution of the United States]]. The first census after the [[American Revolution]] was taken in [[1790 United States census|1790]] under [[United States Secretary of State|Secretary of State]] [[Thomas Jefferson]]. There have been 24 federal censuses since that time.<ref name=decennial/> The census includes [[territories of the United States]].<ref>{{cite web | url=https://www.census.gov/history/www/faqs/demographic_faqs/when_was_puerto_rico_first_included_in_the_us_census.html | title=When was Puerto Rico first included in a census of the United States? - History |website=U.S. Census Bureau }}</ref> The [[United States Census Bureau]] is responsible for conducting the census.

The [[2020 United States census|most recent national census]] took place in 2020; the next census is scheduled for 2030. Since 2013, the Census Bureau began discussions on using technology to aid data collection starting with the 2020 census.<ref>{{cite news|title=2020 Census will be done by Internet|url=https://www.washingtonpost.com/local/2020-census-will-be-done-by-internet/2013/03/28/08453c72-97d8-11e2-b68f-dc5c4b47e519_story.html |url-access=subscription |newspaper=[[The Washington Post]]|access-date=1 April 2013|first=Carol|last=Morello|date=March 28, 2013}}</ref> In 2020, every household received an invitation to complete the census over the Internet, by phone or by paper questionnaire.<ref>{{cite news|title=What You Need To Know About The 2020 Census |date=March 31, 2019 |first1=Hansi Lo |last1=Wang |url=https://www.npr.org/2019/03/31/707899218/what-you-need-to-know-about-the-2020-census|publisher=NPR|access-date=1 April 2019}}</ref><ref>{{cite web |title=Ways to Respond |url=https://2020census.gov/en/ways-to-respond.html |website=U.S. Census Bureau |access-date=20 September 2019 |url-status=dead |archive-url= https://web.archive.org/web/20190920194106/https://2020census.gov/en/ways-to-respond.html |archive-date= Sep 20, 2019 }}</ref> For years between the decennial censuses, the Census Bureau issues estimates made using surveys and statistical models, in particular, the [[Population Estimates Program]] and [[American Community Survey]].

Censuses between [[1940 United States census|1940]] and [[2000 United States census|2000]] (both included) also had a "long form" version, sent to only a subset of the households, with additional questions about socioeconomic and housing characteristics.<ref>{{Cite web |title=Continuity and Change in the U.S. Decennial Census |url=https://www.prb.org/resources/continuity-and-change-in-the-u-s-decennial-census/ |access-date=2025-02-21 |website=PRB |language=en-US}}</ref>

The United States census is distinct from the [[United States Census of Agriculture|Census of Agriculture]], which is no longer the responsibility of the Census Bureau. It is also distinct from local censuses conducted by some states or local [[jurisdiction]]s.

== Legal basis ==
The U.S. census is mandated by [[Article One of the United States Constitution|Article I]], Section 2 of the [[United States Constitution]], which states: "[[United States congressional apportionment|Representatives]] and direct Taxes shall be apportioned among the several States... according to their respective Numbers... . The actual Enumeration shall be made within three years after the [[First United States Congress|first meeting]] of the [[Congress of the United States]], and within every subsequent Term of ten Years".{{efn|[[s:Constitution of the United States of America|Constitution of the United States]]}}<ref name="decennial">{{cite web|url=https://www.census.gov/history/www/programs/demographic/decennial_census.html |title=Decennial Census – History |publisher=U.S. Census Bureau |access-date=2015-03-19}}</ref> Section 2 of the [[Fourteenth Amendment to the United States Constitution|Fourteenth Amendment]] amended Article I, Section 2 to include that the "respective Numbers" of the "several States" will be determined by "counting the whole number of persons in each State, excluding Indians not taxed." The [[United States Census Bureau]] (officially the Bureau of the Census, as defined in Title 13 U.S.C. § 11) is responsible for the United States census. The Bureau of the Census is part of the [[United States Department of Commerce]].

[[Title 13 of the United States Code]] governs how the census is conducted and how its data is handled. Information is confidential as per {{USC|13|9}}. The census law, coupled with the [[Sentencing Reform Act]] of 1984 ([[Title 18 of the United States Code]], Sections 3551, 3559, and 3571), provides for penalties of up to $5,000 for not responding or for willfully providing false answers to any question.

==Procedure==
[[File:Card puncher - NARA - 513295.jpg|thumb|right|A woman with a Hollerith pantograph punch. The keyboard is for the 1940 U.S. census population card.]]
[[File:1940 Census - Fairbanks, Alaska.jpg|thumb|right|This [[1940 United States census|1940 census]] publicity photo shows a census worker in Fairbanks, Alaska. The dog musher remains out of earshot to maintain confidentiality.]]
[[File:Flyers_encouraging_filling_out_the_census_hang_at_Sure_We_Can_-_Brooklyn,_NY_-_2020.jpg|thumb|Census outreach flyers hang at [[Sure We Can]] - redemption center in Bushwick, Brooklyn - 2020]]
Decennial U.S. census figures are based on actual counts of persons dwelling in U.S. residential structures. They include citizens, non-citizen legal residents, non-citizen long-term visitors and undocumented immigrants. The Census Bureau bases its decision about whom to count on the concept of usual residence. Usual residence, a principle established by the Census Act of 1790, is defined as the place a person lives and sleeps most of the time. The Census Bureau uses special procedures to ensure that those without conventional housing are counted. Data from these operations are not as accurate as data obtained from traditional procedures.<ref>{{cite book |last1 = Smith|first1 = Annetta |last2 = Smith|first2 = Denise | title = U.S Census Bureau Census Special Reports Series CENSR/01-2| publisher = US GPO | year = 2001}}</ref>

In instances where the bureau is unsure of the number of residents at an address after a field visit, its population characteristics are inferred from its nearest similar neighbor (hot-deck [[imputation (statistics)#Single imputation|imputation]]). This practice has effects across many areas, but is seen by some as controversial.<ref>{{cite journal | last1 = Meng | first1 = Xiao-Li | year = 1994 | title = Multiple-Imputation Inferences with Uncongenial Sources of Input | journal = Statistical Science | volume = 9 | issue = 4 | pages = 538–558 | jstor =2246252 | doi = 10.1214/ss/1177010269| doi-access = free }}</ref> The practice was ruled constitutional by the [[Supreme Court of the United States|U.S. Supreme Court]] in ''[[Utah v. Evans]]''.

Certain American citizens living overseas are specifically excluded from being counted in the census even though they may vote. Only Americans living abroad who are "federal employees (military and civilian) and their dependents living overseas with them" are counted. "Private U.S. citizens living abroad who are not affiliated with the federal government (either as employees or their dependents) will not be included in the overseas counts. These overseas counts are used solely for [[United States congressional apportionment|reapportioning seats in the U.S. House of Representatives]]".<ref>{{cite web |title=Census Help |url=https://ask.census.gov/prweb/PRServletCustom?pyActivity=pyMobileSnapStart&ArticleID=KCP-2692 |website=ask.census.gov |publisher=[[United States Census Bureau]] |access-date=17 June 2017 |archive-url=https://web.archive.org/web/20180104202729/https://ask.census.gov/prweb/PRServletCustom/YACFBFye-rFIz_FoGtyvDRUGg1Uzu5Mn*/!STANDARD?pyActivity=pyMobileSnapStart&ArticleID=KCP-2692 |archive-date=4 January 2018 |url-status=live }}</ref>

According to the Census Bureau, "Census Day" has been April 1 since 1930. Previously, from 1790 to 1820, the census counted the population as of the first Monday in August. It moved to June 1 in 1830, June 2 in 1890, April 15 in 1910, and January 1 in 1920.<ref>{{cite web |url=https://www.census.gov/history/ |title=History. U.S. Census Bureau |publisher=U.S. Census Bureau}}</ref>

Because people are born, die, and move during the year, the census counts people where they were or expect to be living on this specific reference date in an attempt to get a coherent snapshot and avoid double counting. The actual census-taking begins before this date and extends for months thereafter. In 2020, the earliest responses were collected starting January 21 in remote parts of Alaska, and March 12 for most Americans.<ref name="myths">[https://www.npr.org/2020/03/05/809217188/10-census-facts-that-bust-common-myths-about-the-2020-u-s-head-count 10 Census Facts That Bust Common Myths About The 2020 U.S. Head Count]</ref>

== Applications ==

In addition to its primary purpose of reapportioning the House of Representatives, census data are used for a wide variety of applications, including:
* Apportionment of federal funding in a large number of programs, estimated at somewhere between $675&nbsp;billion and $1.5&nbsp;trillion per year.<ref name="myths" />
* Infrastructure and [[transportation planning]] 
* Military and disaster response planning
* Economic analysis
* Commercial investment and marketing decisions
* Computer programs that can disambiguate place names based on which has the highest population
* General reference works

==Controversy==
{{Update|section|date=August 2019}}
[[File:Gavin Newsom promoting the US Census - 2020-08-09.ogg|thumb|California Governor [[Gavin Newsom]] encouraging people to complete the [[2020 United States census]].]]
The census has historically and up to the present been controversial due to its role in reapportioning political representation.<ref name=":1">{{Cite journal|last1=Ruggles|first1=Steven|last2=Magnuson|first2=Diana L|date=2020|title=Census Technology, Politics, and Institutional Change, 1790–2020|journal=Journal of American History|volume=107|issue=1|pages=19–51|doi=10.1093/jahist/jaaa007|pmid=34483359 |pmc=8415740|issn=0021-8723|doi-access=free}}</ref> In the 1850s, census planners suppressed information about slavery due to pressure from Southern lawmakers.<ref name=":1" /> The results of the 1920 census were ignored and no reapportionment took place, as rural lawmakers feared losing power to urban areas.<ref name=":1" /> In the 1940s, census officials were involved in organizing [[Internment of Japanese Americans|Japanese-American internment]].<ref name=":1" />

The census is controversial; up to one-third of all U.S. residents do not respond to repeated reminders. In recent censuses, the nonresponse rate has been less than 1% (it was about 0.4% in 2010), but during the 2020 census, as of September 11, many experts believed the nonresponse rate could reach double digits.<ref name=":0">{{Cite journal|last=Mervis|first=Jeffrey|date=2020-09-11|title=Census experts fear rush to finish tally will yield flawed data|url=https://www.science.org/doi/10.1126/science.369.6509.1285|journal=Science|language=en|volume=369|issue=6509|pages=1285–1286|doi=10.1126/science.369.6509.1285|pmid=32913083|bibcode=2020Sci...369.1285M|s2cid=221625047 |issn=0036-8075|url-access=subscription}}</ref> By October 19, 2020, all states had topped a 99% response rate, with all but one state having a nonresponse rate below 0.1%.<ref>{{Cite web   |title=2020 Census Response Rate Update: 99.98% Complete Nationwide |url=https://www.census.gov/newsroom/press-releases/2020/2020-census-all-states-top-99-percent.html |access-date=2022-07-31 |website=Census.gov}}</ref>

The Census Bureau estimates that in 1970 over six percent of African Americans went uncounted, whereas only around two percent of European Americans<ref>{{cite web|url=https://www.ssc.wisc.edu/soc/racepoliticsjustice/2017/09/16/race-names/|title=Race Names: Talking and teaching about race|publisher=University of Wisconsin-Madison|date=16 September 2017}} The easiest way to avoid serious offense is to stick with the continent names (European, African, Asian, American).</ref> went uncounted. Democrats often argue that modern sampling techniques should be used so that more accurate and complete data can be inferred. Republicans often argue against such sampling techniques, stating the U.S. Constitution requires an "actual enumeration" for apportionment of House seats, and that political appointees would be tempted to manipulate the sampling formulas.<ref>{{cite news|title=Why People Fight So Much About the Census|url=https://www.washingtonpost.com/wp-srv/politics/daily/aug98/census30.htm|access-date=29 April 2014|newspaper=[[Washington Post]]|date=30 August 1998|author=Michael Teitelbaum|author2=Jay Winter}}</ref>

Groups like the [[Prison Policy Initiative]] assert that the census practice of counting prisoners as residents of prisons, not their pre-incarceration addresses, leads to misleading information about racial demographics and population numbers.<ref>{{cite web |url=http://www.prisonersofthecensus.org/impact.html |title=The Problem |publisher=Prisoners of the Census |date=September 26, 2005 |access-date=2010-03-24}}</ref>

=== 2020 ===
{{main|2020 United States census}}
The 2020 census drew a number of controversies and legal challenges under the [[First presidency of Donald Trump|Trump administration]] due to President [[Donald Trump]]'s policies on illegal immigration, particularly those undocumented in the country. Prior to the publication of the census, the Commerce Department stated its intention to add a question asking responders about their immigration status, which many states and activists stated would cause illegal immigrants to not respond out of fear of prosecution and lead to undercounting, affecting state representation and federal funding.<ref>{{cite web |url=https://www.yahoo.com/news/why-census-asking-citizenship-problem-175053088.html/| title=Why the census asking about citizenship is such a problem |last=Weiser |first=Wendy |date=March 27, 2018 |work=Huff Post |access-date=March 28, 2018}}</ref><ref>{{Cite news|url=https://www.usatoday.com/story/news/nation/2018/03/27/california-sues-trump-administration-over-census-citizenship-question/462241002/|title=California sues Trump administration over Census citizenship question|last=Gomez|first=Alan|date=March 27, 2018|work=USA Today|access-date=March 27, 2018}}</ref> The Supreme Court case ''[[Department of Commerce v. New York]]'', decided in June 2019, found the rationale to add the question was [[arbitrary and capricious]] and required the department to provide a better reasoning before inclusion. The department dropped the question by the form's publication time.<ref>{{cite news|url=https://www.nytimes.com/2019/06/27/us/politics/census-citizenship-question-supreme-court.html|title=Supreme Court Leaves Census Question on Citizenship in Doubt|first=Adam|last=Liptak|date=June 27, 2019|newspaper=The New York Times}}</ref> Following the decision, Trump issued an executive order directing the department to obtain citizenship data from other federal agencies rather than via the census.<ref>{{cite news |title=Trump backs away from census citizenship question, direct agencies to hand over citizenship information to Commerce |url=https://www.cnn.com/2019/07/11/politics/trump-census-executive-action/index.html |access-date=February 27, 2020 |issue=July 11, 2019 |publisher=CNN}}</ref> On July 21, 2020, Trump signed a [[presidential memorandum]] ordering the exclusion of illegal immigrants from the numbers in the 2020 census that are used to apportion seats in the House of Representatives.<ref>{{cite web|url=https://www.npr.org/2020/07/21/892340508/with-no-final-say-trump-wants-to-change-who-counts-for-dividing-up-congress-seat|title=With No Final Say, Trump Wants to Change Who Counts for Dividing up Congress' Seats|website=[[NPR]] }}</ref>

The [[COVID-19 pandemic]] made the collection of the census results difficult, and the department had extended the deadline to complete collection to October 31 instead of July 31, 2020. On August 3, the department announced its Replan Schedule that would end collection early on September 30, aware this would leave them with incomplete data that they would have to estimate total numbers to complete. This move was again challenged in the courts. While lower courts had ruled for an injunction against the department from implementing the Replan Schedule, the Supreme Court issued a stay of the injunction in October 2020, allowing the census to end early.<ref>{{cite news | url = https://www.nytimes.com/2020/10/13/us/supreme-court-census.html | title = Supreme Court Rules That Census Count Can Be Cut Short | first1 = Adam | last1 = Liptak | first2 = Michael | last2 = Wines | date = October 13, 2020 | access-date = October 18, 2020 | work = [[The New York Times]] }}</ref>

Around the same time, Trump issued a memo to the Commerce Department on July 21, 2020, instructing them to use estimates of undocumented immigrants and subtract their numbers from the totals, claiming that he had the authority to make this determination on a Constitutional and past legal basis.<ref name=":0" /> Several legal challenges were filed, and a combined suit from 22 states and several non-governmental organizations were found against Trump, ruling that only Congress has the authority to interpret the manner of which people the census includes. Trump petitioned to the Supreme Court which has certified the case ''[[Trump v. New York]]'' for an expedited hearing in November, given the results are to be delivered to Congress by December 31, 2020.<ref>{{cite news | url = https://www.washingtonpost.com/politics/courts_law/supreme-court-census-undocumented-immigrants/2020/10/16/cf8288be-0f51-11eb-8074-0e943a91bf08_story.html | title= Supreme Court will review Trump plan to exclude undocumented immigrants from calculations for congressional seats | first=  Robert | last =Barnes | date = October 16, 2020 | access-date= October 16, 2020 | newspaper = [[The Washington Post]] }}</ref> The Court issued a per curiam decision on December 18, 2020, which vacated the District Court's ruling and remanded the case to that court with orders to dismiss it.

==History==
[[File:Francis William Edmonds - Taking the Census.jpg|thumb|''Taking the Census'' by [[Francis William Edmonds]] (1854) is the earliest known depiction of the census-taking process.<ref>{{Cite web |url=https://www.metmuseum.org/art/collection/search/10423 |title=Taking the Census |access-date=2023-06-05 |website=metmuseum.org |archive-url=https://web.archive.org/web/20221026162402/https://www.metmuseum.org/art/collection/search/10423 |archive-date=2022-10-26 |url-status=live |publisher=[[Metropolitan Museum of Art]]}}</ref>]]

Censuses had been taken prior to the Constitution's ratification; in the early 17th century, a census was taken in [[Virginia]], and people were counted in almost all of the British colonies that became the [[United States]].<ref>{{cite book|last=Sutherland|first=Stella H.|title=Bicentennial Edition: Historical Statistics of the United States, Colonial Times to 1970, Part 2|url=https://www2.census.gov/library/publications/1975/compendia/hist_stats_colonial-1970/hist_stats_colonial-1970p2-chZ.pdf|page=1168|date=1975|publisher=[[U.S. Census Bureau]]|location=Washington, D.C.}}</ref> Between 1781 and 1786, the first "actual enumeration" was conducted separately in each state and compiled by [[John Kean (South Carolina politician)|John Kean]] for consideration at the [[Constitutional Convention (United States)|Constitutional Convention]] in 1787.<ref>{{Cite news |last=Roberts |first=Sam |date=May 19, 2010 |title=Early Census Is Found in a New Jersey University's Files |language=en-US |work=[[The New York Times]] |location=New York City, New York |url=https://www.nytimes.com/2010/05/19/nyregion/19kean.html |access-date=June 6, 2022 |issn=0362-4331}}</ref>

Throughout the years, the country's needs and interests became more complicated. This meant that statistics were needed to help people understand what was happening and have a basis for planning. The content of the decennial census changed accordingly. In 1810, the first inquiry on manufactures, quantity and value of products occurred; in 1840, inquiries on fisheries were added; and in 1850, the census included inquiries on social issues, such as taxation, churches, pauperism, and crime. The censuses also spread geographically, to new states and territories added to the Union, as well as to other areas under U.S. sovereignty or jurisdiction. There were so many more inquiries of all kinds in the census of 1880 that almost a full decade was needed to publish all the results. In response to this, the census was mechanized in 1890, with [[tabulating machine]]s made by [[Herman Hollerith]]. This reduced the processing time to two and a half years.<ref>Martin Campbell-Kelly and William Aspray, "Computer a History of the Information Machine – Second Edition", Westview Press, pp. 14–19 2004</ref>

For the first six censuses (1790–1840), enumerators recorded only the names of the heads of household and a general demographic accounting of the remaining members of the household. Beginning in 1850, all members of the household were named on the census. The first slave schedules were also completed in 1850, with the second (and last) in 1860. Censuses of the late 19th century also included agricultural and industrial schedules to gauge the productivity of the nation's economy. Mortality schedules (taken between 1850 and 1880) captured a snapshot of life spans and causes of death throughout the country.

The first nine censuses (1790–1870) were conducted by U.S. Marshals before the Census Bureau was created.<ref>{{cite web|url=https://www.usmarshals.gov/history/broad_range.htm|title=United States Marshals and Their Deputies: 1789-1989 |website=U.S. Marshals Service }}</ref> Appointed U.S. Marshals of each judicial district hired assistant marshals to conduct the actual enumeration. The census enumerators were typically from the village or neighborhood and often knew the residents. Before enabling self-identification on the censuses, the U.S. Census Bureau relied on local people to have some knowledge of residents. Racial classification was made by the census enumerator in these decades, rather than by the individual.
{{sticky header}}
{| class="sortable wikitable sticky-header"
|-
! Year
!  Total population
!  Change in population
!  Most populated state
!  Most populated city
!Ethnic demographics counted<ref>{{cite web|title=Measuring Race and Ethnicity Across The Decades: 1790—2010 |url=https://www.census.gov/data-tools/demo/race/MREAD_1790_2010.html|access-date=2020-06-26|website=U.S. Census Bureau }}</ref>
!  Slaves
!  Notes
|- valign="top"
| style="text-align:center;"| [[1790 United States census|1790]]{{Efn|August 2, 1790}}
| style="text-align:right;"|3,929,326{{Efn|The number originally published in 1790 was 3,893,635.}}
| style="text-align:center;"|—
| style="text-align:right;"|[[File:Seal of Virginia (1714).png|15px]] [[Virginia]]<br />{{small|(747,610)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(33,131)}}
|Free [[White people|white females and males]], other free persons, [[Slavery in the United States|slaves]]
| style="text-align:right;"|694,280
| Original numbers were corrected later.
|- valign="top"
| style="text-align:center;"| [[1800 United States census|1800]]{{Efn|August 4, 1800}}
| style="text-align:right;"|5,308,483{{Efn|The number originally published in 1800 was 5,172,312.}}
| style="text-align:right;"|{{increase}} 35%
| style="text-align:right;"|[[File:Seal of Virginia (1714).png|15px]] [[Virginia]]{{Efn|At the time of the 1800 Census, the territory donated to form the District of Columbia was still being administered by the states of Maryland and Virginia. The state of Maryland included the population of the District under its control within its own return. The population of the District of Columbia within Maryland was 8,144 persons, including 5,672 whites, 400 free blacks, and 2,472 enslaved persons.}}<br />{{small|(676,682)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(60,515)}}
|Free white females and males, other free persons, slaves
| style="text-align:right;"|893,605{{Efn|The number originally published in 1800 was 875,626.}}
| Original numbers were corrected later.
|- valign="top"
| style="text-align:center;"| [[1810 United States census|1810]]{{Efn|August 6, 1810}}
| style="text-align:right;"|7,239,881
| style="text-align:right;"|{{increase}} 36%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(959,049)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(96,373)}}
|Free white females and males, other free persons, slaves
| style="text-align:right;"|1,191,362
|The authorizing act of the third census stipulated that each marshal (enumerator) must personally visit each household, rather than rely on hearsay.
|- valign="top"
| style="text-align:center;"| [[1820 United States census|1820]]{{Efn|August 7, 1820}}
| style="text-align:right;"|9,638,453
| style="text-align:right;"|{{increase}} 33%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(1,372,812)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(123,706)}}
|Free white females and males, other free persons, [[free people of color]], slaves
| style="text-align:right;"|1,538,022
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1830 United States census|1830]]{{Efn|June 1, 1830}}
| style="text-align:right;"|12,866,020
| style="text-align:right;"|{{increase}} 33%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(1,918,608)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(202,589)}}
|Free white females and males, other free persons, free people of color, slaves
| style="text-align:right;"|2,009,043
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1840 United States census|1840]]{{Efn|June 1, 1840}}
| style="text-align:right;"|17,069,453
| style="text-align:right;"|{{increase}} 33%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(2,428,921)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(312,710)}}
|Free white females and males, other free persons, free people of color, slaves
| style="text-align:right;"|2,487,355
| The census estimated the [[population of the United States]] at 17,100,000. The results were tabulated by 28 clerks in the Bureau of the Census.
|- valign="top"
| style="text-align:center;"| [[1850 United States census|1850]]{{Efn|June 1, 1850}}
| style="text-align:right;"|23,191,876
| style="text-align:right;"|{{increase}} 36%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(3,097,394)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(515,547)}}
|[[Black people|Black]], [[Mulatto]], White
| style="text-align:right;"|3,204,313
| The 1850 census was a landmark year in American census-taking. It was the first year in which the census bureau attempted to record every member of every household, including women, children and slaves. Accordingly, the first slave schedules were produced in 1850. Prior to 1850, census records had only recorded the name of the head of the household and tabulated the other household members within given age groups.
|- valign="top"
| style="text-align:center;"| [[1860 United States census|1860]]{{Efn|June 1, 1860}}
| style="text-align:right;"|31,443,321
| style="text-align:right;"|{{increase}} 35%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(3,880,735)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(813,669)}}
|[[Native Americans in the United States|Indian]], [[Chinese people|Chinese]], Black, Mulatto, White
| style="text-align:right;"|3,953,761
| The results were tabulated by 184 clerks in the Bureau of the Census. This was the first census where American indigenous people officially were counted, but only those who had 'renounced tribal rules'. The figure for the nation was 40,000.
|- valign="top"
| style="text-align:center;"| [[1870 United States census|1870]]{{Efn|June 1, 1870}}
| style="text-align:right;"|39,818,449{{Efn|The number originally published in 1870 was 38,555,983.}}
| style="text-align:right;"|{{increase}} 23%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(4,382,759)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(942,292)}}
|Indian, Chinese, Black, Mulatto, White
| rowspan="16" style="text-align:center;" |{{center|—}}
| The first census to provide detailed information on the black population, only years after the culmination of the Civil War when slaves were granted freedom. The results are controversial, as many believed it underestimated the true population numbers, especially in New York and Pennsylvania.
|- valign="top"
| style="text-align:center;"| [[1880 United States census|1880]]{{Efn|June 1, 1880}}
| style="text-align:right;"|50,189,209
| style="text-align:right;"|{{increase}} 30%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(5,082,871)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(1,206,299)}}
|Indian, Chinese, Black, Mulatto, White
| The first census that permitted women to be enumerators. Also led to the discovery of [[Alabama paradox]].
|- valign="top"
| style="text-align:center;"| [[1890 United States census|1890]]{{Efn|June 2, 1890}}<ref group="n">Taken one day late because June 1 was a Sunday.</ref>
| style="text-align:right;"|62,947,714
| style="text-align:right;"|{{increase}} 25%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(6,003,174)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(1,515,301)}}
|Indian, Chinese, [[Japanese people|Japanese]], Black, Mulatto, [[Quadroon]], [[Octaroon]], White 
| Because it was believed that the frontier region of the United States no longer existed, the tracking of westward migration was not tabulated in the 1890 census.<ref>{{cite book |last1 = Porter |first1 = Robert |last2 = Gannett |first2 = Henry |last3 = Hunt |first3 = William | title = "Progress of the Nation", in "Report on Population of the United States at the Eleventh Census: 1890, Part 1" | pages = xviii–xxxiv | publisher = Bureau of the Census | year = 1895}}</ref> This trend prompted [[Frederick Jackson Turner]] to develop his milestone [[Frontier Thesis]].<br />
The 1890 census was the first to be compiled using the new [[tabulating machines]] invented by [[Herman Hollerith]]. The net effect of the many changes from the 1880 census (the larger population, the number of data items to be collected, the Census Bureau headcount, the volume of scheduled publications, and the use of Hollerith's electromechanical tabulators) was to reduce the time required to fully process the census from eight years for the [[U.S. Census, 1880|1880 census]] to six years for the 1890 census.<ref name="11th census report">{{cite book |title=Report of the Commissioner of Labor In Charge of The Eleventh Census to the Secretary of the Interior for the Fiscal Year Ending June 30, 1895 |location=Washington, DC |publisher=[[United States Government Publishing Office]] |date=July 29, 1895 |oclc=867910652|hdl=2027/osu.32435067619882 }} p. 9: "You may confidently look for the rapid reduction of the force of this office after the 1st of October, and the entire cessation of clerical work during the present calendar year. ... The condition of the work of the Census Division and the condition of the final reports show clearly that the work of the Eleventh Census will be completed at least two years earlier than was the work of the Tenth Census." — Carroll D. Wright, Commissioner of Labor in Charge</ref> The total population, of 62,947,714, was announced after only six weeks of processing (punched cards were not used for this family, or ''rough'', count).<ref>{{cite web |url=http://www2.census.gov/prod2/statcomp/documents/1991-02.pdf |title=Population and Area (Historical Censuses) |publisher=United States Census Bureau}}</ref><ref>[[Leon E. Truesdell|Truesdell, Leon E.]] (1965) The Development of Punch Card Tabulation in the Bureau of the Census 1890–1940, US GPO, p. 61</ref> The public reaction to this tabulation was disbelief, as it was widely believed that the "right answer" was at least 75,000,000.<ref>Austrian, Geoffrey D. (1982) ''Herman Hollerith – Forgotten Giant of Information Processing'', Columbia, pp. 85–86</ref>
<br />
This census is also notable for the fact it is one of only three for which the original data are no longer available. Almost all the population schedules were destroyed following a fire in 1921.
|- valign="top"
| style="text-align:center;"| [[1900 United States census|1900]]{{Efn|June 1, 1900}}
| style="text-align:right;"|76,212,168
| style="text-align:right;"|{{increase}} 21%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(7,268,894)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(3,437,202)}}
|Indian, Chinese, Japanese, Black ([[Negro|Negro or of Negro descent]]), White
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1910 United States census|1910]]{{Efn|April 15, 1910}}
| style="text-align:right;"|92,228,496
| style="text-align:right;"|{{increase}} 21%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(9,113,614)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(4,766,883)}}
|Indian, Chinese, Japanese, Black (Negro), Mulatto, White, other
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1920 United States census|1920]]{{Efn|January 1, 1920}}
| style="text-align:right;"|106,021,537
| style="text-align:right;"|{{increase}} 15%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(10,385,227)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(5,620,048)}}
|Indian, Chinese, [[Filipinos|Filipino]], [[Hindus|Hindu]], Japanese, [[Koreans|Korean]], Black (Negro), Mulatto, White, other
| This was the first census that recorded a population exceeding 100&nbsp;million.
|- valign="top"
| style="text-align:center;"| [[1930 United States census|1930]]{{Efn|April 1, 1930}}<ref group="n">In the [[Alaska Territory]], census-taking began on October 1, 1929.</ref>
| style="text-align:right;"|122,775,046
| style="text-align:right;"|{{increase}} 13%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(12,588,066)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(6,930,446)}}
|Indian, Chinese, Filipino, Hindu, Japanese, Korean, Negro, [[Mexicans|Mexican]], White, other
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1940 United States census|1940]]{{Efn|April 1, 1940}}
| style="text-align:right;"|132,164,569
| style="text-align:right;"|{{increase}} 7%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(13,479,142)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,454,995)}}
|Indian, Chinese, Filipino, Hindu, Japanese, Korean, Negro, White, other
| style="text-align:center;"|—
|- valign="top"
| style="text-align:center;"| [[1950 United States census|1950]]{{Efn|April 1, 1950}}
| style="text-align:right;"|150,697,361
| style="text-align:right;"|{{increase}} 14%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(14,830,192)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,891,957)}}
|American Indian, Chinese, Filipino, Japanese, Negro, White, other
| The most recent census where individuals' data have now been released to the public (by the [[72-year rule]]).
|- valign="top"
| style="text-align:center;"| [[1960 United States census|1960]]{{Efn|April 1, 1960}}
| style="text-align:right;"|179,323,175
| style="text-align:right;"|{{increase}} 19%
| style="text-align:right;"|[[File:Seal of New York.svg|15px]] [[New York (state)|New York]]<br />{{small|(16,827,000)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,781,984)}}
|[[Aleut]], American Indian, [[Eskimo]], Chinese, Filipino, Japanese, Negro, [[Native Hawaiians|Hawaiian, part-Hawaiian]], White
| Will be available for public inspection on April 1, 2032.
|- valign="top"
| style="text-align:center;"| [[1970 United States census|1970]]{{Efn|April 1, 1970}}
| style="text-align:right;"|203,302,031
| style="text-align:right;"|{{increase}} 13%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(19,953,134)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,894,862)}}
|American Indian, Chinese, Filipino, Japanese, Korean, Negro or Black, [[Hispanic|Hispanic origin]], Mexican, [[Puerto Ricans|Puerto Rican]], [[Cubans|Cuban]], [[Central America|Central]] or [[South America]]n, Hawaiian, White, other
| The first census that recorded a population exceeding 200&nbsp;million. Will be available for public inspection on April 1, 2042.
|- valign="top"
| style="text-align:center;"| [[1980 United States census|1980]]{{Efn|April 1, 1980}}
| style="text-align:right;"|226,545,805
| style="text-align:right;"|{{increase}} 11%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(23,667,902)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,071,639)}}
|Aleut, Eskimo, American Indian, [[Indian Americans|Asian Indian]], Chinese, Filipino, Japanese, Korean, [[Vietnamese people|Vietnamese]], Black or Negro, Hispanic origin, Mexican, [[Mexican Americans|Mexican-American]], [[Chicano]], Puerto Rican, Cuban, other Hispanic, Hawaiian, [[Chamorro people|Guamanian]], [[Samoans|Samoan]], White, other
| Will be available for public inspection on April 1, 2052.
|- valign="top"
| style="text-align:center;"| [[1990 United States census|1990]]{{Efn|April 1, 1990}}
| style="text-align:right;"|248,709,873
| style="text-align:right;"|{{increase}} 10%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(29,760,021)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(7,322,564)}}
|Aleut, Eskimo, American Indian, [[Asian Pacific American|Asian or Pacific Islander]], Chinese, Filipino, Korean, Vietnamese, Japanese, Asian Indian, other [[Asian Pacific American|API]], Black or Negro, Hispanic origin, Mexican, Mexican-American, Chicano, Puerto Rican, Cuban, other Hispanic, Hawaiian, Guamanian, Samoan, White, other race
| Will be available for public inspection on April 1, 2062.
|- valign="top"
| style="text-align:center;"| [[2000 United States census|2000]]{{Efn|April 1, 2000}}
| style="text-align:right;"|281,421,906
| style="text-align:right;"|{{increase}} 13%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(33,871,648)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(8,008,278)}}
|American Indian, [[Alaska Natives|Alaska Native]], Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, other Asian, Black, [[African Americans|African American]], or Negro, Hispanic origin, Mexican, Mexican-American, Chicano, Puerto Rican, Cuban, other Hispanic, Hawaiian, Guamanian or Chamorro, Samoan, other Pacific Islander, White, other race
| Will be available for public inspection on April 1, 2072.
|- valign="top"
| style="text-align:center;"| [[2010 United States census|2010]]{{Efn|April 1, 2010}}
| style="text-align:right;"|308,745,538
| style="text-align:right;"|{{increase}} 10%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(37,253,956)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(8,175,133)}}
|American Indian, Alaska Native, Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, other Asian, Black, African American, or Negro, Hispanic origin, Mexican, Mexican-American, Chicano, Puerto Rican, Cuban, other Hispanic, Hawaiian, Guamanian or Chamorro, Samoan, other Pacific Islander, White, other race
| The first short-form-only census since 1940, as the decennial long form has been replaced by the [[American Community Survey]]. The first census that recorded a population exceeding 300&nbsp;million. Will be available for public inspection on April 1, 2082.
|- valign="top"
| style="text-align:center;"| [[2020 United States census|2020]]{{Efn|April 1, 2020}}
| style="text-align:right;"|331,449,281
| style="text-align:right;"|{{increase}} 7%
| style="text-align:right;"|[[File:Seal of California.svg|15px]] [[California]]<br />{{small|(39,538,223)}}
| style="text-align:right;"|[[File:Seal of New York City BW.svg|15px]] [[New York City|New York]], [[New York (state)|NY]]<br />{{small|(8,804,190)}}
|American Indian, Alaska Native, Asian Indian, Chinese, Filipino, Japanese, Korean, Vietnamese, other Asian, Chamorro, Native Hawaiian, Samoan, other Pacific Islander, Black or African American, Hispanic, Latino or Spanish origin, Chicano, Cuban, Mexican, Mexican American, Puerto Rican, another Hispanic origin, White, some other race
| The first U.S. census to offer options to respond online or by phone, in addition to the option to respond on a paper form as with previous censuses. Will be available for public inspection on April 1, 2092.
|}
{{Reflist|group=n}}
[[File:Census2010LogoMN.png|thumb|Census regional marketing logo in [[Minnesota]].]]

==Respondent confidentiality==
One purpose of the census is to divide the house seats by population. Furthermore, as with any Census Bureau survey, the data provides a beginning for the allocation of resources. In addition, collected data are used in aggregate for statistical purposes.<ref>{{cite web|url=http://www.thisnation.com/question/022.html|title=What is the purpose of the Census? What is the data used for?|date=October 11, 2021 }}</ref> Replies are obtained from individuals and establishments only to enable the compilation of such general statistics. The confidentiality of these replies is very important. By law, no one—neither the census takers nor any other Census Bureau employee—is permitted to reveal identifiable information about any person, household, or business.

By law ({{USStatute|95|416|92|915|1978|October|5}}), individual decennial census records are sealed for 72 years.<ref>{{cite web|url=https://www.census.gov/history/www/genealogy/decennial_census_records/the_72_year_rule_1.html |title=The "72-Year Rule" | publisher=U.S. Census Bureau}}</ref> One explanation for this number is that it was chosen in 1952<ref>{{cite web|url=https://www.npr.org/2012/04/02/149575704/the-1940-census-72-year-old-secrets-revealed |title=The 1940 Census: 72-Year-Old Secrets Revealed|website=[[NPR]] }}</ref> as slightly higher than the average female life expectancy, 71.6.<ref>{{cite web |url=http://demog.berkeley.edu/~andrew/1918/figure2.html |title=Life expectancy in the USA, 1900–98 |access-date=June 8, 2015 |archive-url=https://web.archive.org/web/20160326234944/http://www.demog.berkeley.edu/~andrew/1918/figure2.html |archive-date=March 26, 2016 |url-status=dead }}</ref> Another explanation (which disputes the life expectancy number) is that this number is a holdover from 1942, when a disagreement between the Census Bureau and the National Archives was resolved with 1870 as the boundary between confidential and public records.<ref>{{cite web|url=https://www.npr.org/2022/02/04/1074566938/census-data-72-year-rule-privacy-policy-confidentiality |title=Why you have to wait 72 years for census records to be released |first1=Hansi Lo |last1=Wang |first2=Susie |last2=Cummings |publisher=NPR |date=2022-02-04 |accessdate=2022-03-18}}</ref> The individual census data most recently released to the public is the 1950 census, released on April 1, 2022. Aggregate census data are released when available.

===FBI data use===
Under the administration of President [[Franklin D. Roosevelt]], the [[Federal Bureau of Investigation]] (FBI), using primarily census records, compiled (1939–1941) the [[Custodial Detention Index]] ("CDI") on [[U.S. citizen|citizens]], [[enemy aliens]], and [[foreign national]]s, who might be dangerous. The [[War Powers Act of 1941|Second War Powers Act of 1941]] repealed the legal protection of confidential census data, which was not restored until 1947. This information facilitated the [[Japanese American internment|internment of Japanese-Americans]], following the [[Empire of Japan|Japanese]] [[Attack on Pearl Harbor|attack on the U.S. at Pearl Harbor]] on December 7, 1941, and the internment of [[Italian American internment|Italian-]] and [[German American internment|German-Americans]] following the United States' entry into [[World War II]].<ref>{{cite web|url=http://www.sciam.com/article.cfm?articleID=A4F4DED6-E7F2-99DF-32E46B0AC1FDE0FE&sc=I100322|title=Confirmed: The U.S. Census Bureau Gave Up Names of Japanese-Americans in WW II|date=2007-03-30|publisher=Scientific American |first=JR |last=Minkel |access-date=2009-11-02}}</ref><ref>{{cite news|url=https://www.usatoday.com/news/nation/2007-03-30-census-role_N.htm|title=Papers show Census role in WWII camps|date=2007-03-30|publisher=[[USA Today]] |first=Haya |last=El Nasser |access-date=2009-11-02}}</ref>

In 1980, four FBI agents went to the Census Bureau's [[Colorado Springs, Colorado|Colorado Springs]] office with [[search warrant|warrants]] to seize census documents, but were forced to leave with nothing. Courts upheld that no agency, including the FBI, has access to census data.<ref>{{cite news|url=http://findarticles.com/p/articles/mi_qn4191/is_20000324/ai_n9965696/|archive-url=https://web.archive.org/web/20100605013514/http://findarticles.com/p/articles/mi_qn4191/is_20000324/ai_n9965696/|url-status=dead|archive-date=June 5, 2010|first=Mary |last=Boyle|title=Springs once tested Census' confidentiality|date=March 24, 2000|publisher=[[The Gazette (Colorado Springs)]]}}</ref>

==Data analysis==
The census records data specific to individual respondents are not available to the public until 72 years after a given census was taken, but aggregate statistical data derived from the census are released as soon as they are available. Every census up to and including [[1950 United States census|1950]] is currently available to the public and can be viewed on [[microform|microfilm]] released by the [[National Archives and Records Administration]], the official keeper of archived federal census records. Complete online census records can be accessed for no cost from National Archives facilities and many libraries,<ref>{{cite web|title=How can I search the Census Records?|author=National Archives and Records Administration|url=https://www.archives.gov/genealogy/census/research.html|access-date=December 13, 2008|archive-url=https://web.archive.org/web/20081217082120/http://www.archives.gov/genealogy/census/research.html|archive-date=2008-12-17|url-status=dead}}</ref> and a growing portion of the census is freely available from non-commercial online sources.<ref>{{cite web|url=http://pilot.familysearch.org/recordsearch|title=Discover your Ancestors|url-status=dead|archive-url=https://web.archive.org/web/20081226191337/http://pilot.familysearch.org/recordsearch/|archive-date=2008-12-26}}</ref><ref>{{cite web |url=http://www.usgwcensus.org/ |title=The USGenWeb Free Census Project |access-date=2010-03-24}}</ref><ref>{{cite web |url=http://www.us-census.org/ |title=The USGenWeb Census Project |access-date=2010-03-24}}</ref>

Census [[microdata (statistics)|microdata]] for research purposes are available for all censuses from [[1790 United States census|1790]] forward except for 1890 through the Integrated Public Use Microdata Series ([[IPUMS]]), and scanned copies of each of the decennial census questionnaires are available online from many websites. Computerized [[aggregate data]] describing the characteristics of small geographic areas for the entire period from [[1790 United States census|1790]] to [[2010 United States census|2010]] are available from the [[National Historical Geographic Information System]].

===Regions and divisions===
[[File:US Census geographical region map.png|right|thumb|US Census Bureau Population Regions]]
The bureau recognizes four census [[Census Bureau Division|regions]] within the United States and further organizes them into nine divisions. These regions are groupings of states that subdivide the United States for the presentation of data.

{| class="wikitable"
|-
! colspan="4" | U.S. census regions
|-
! valign="top" | Region 1: [[Northeastern United States|Northeast]]
! valign="top" | Region 2: [[Midwestern United States|Midwest]]
! valign="top" | Region 3: [[Southern United States|South]]
! valign="top" | Region 4: [[Western United States|West]]
|-
| valign="top" |
* Division 1: [[New England]]
* Division 2: [[Mid-Atlantic States|Mid-Atlantic]]
| valign="top" |
* Division 3: [[East North Central States|East North Central]]
* Division 4: [[West North Central States|West North Central]]
| valign="top" |
* Division 5: [[South Atlantic States|South Atlantic]]
* Division 6: [[East South Central States|East South Central]]
* Division 7: [[West South Central States|West South Central]]
| valign="top" |
* Division 8: [[Mountain States|Mountain]]
* Division 9: [[Pacific States|Pacific]]
|}

===Poverty measures===
The '''official poverty measure''' (OPM), in use in America since the 1960s, defines poverty by comparing '''pre-tax money income''' to a poverty threshold that is adjusted by family composition. The pre-tax money income excludes the value of government noncash benefits provided either privately or publicly, such as health insurance, [[Supplemental Nutrition Assistance Program|food stamps]], or housing assistance.<ref>[https://crsreports.congress.gov/product/pdf/R/R45031 The Supplemental Poverty Measure: Its Core Concepts, Development, and Use]</ref> The threshold was derived from the cost of a minimum food diet multiplied by three to account for other family expenses.<ref>{{cite web |title=The History of the Official Poverty Measure |url=https://www.census.gov/topics/income-poverty/poverty/about/history-of-the-poverty-measure.html |website=census.gov |publisher=[[United States Census Bureau]] |access-date=2 April 2025 |language=en}}</ref>

The '''supplemental poverty measure''' (SPM), introduced in 2011, aims to provide a more accurate picture of the true extent of [[poverty in the United States]] than the OPM, by taking into account non-cash benefits and geographic variations in the [[cost-of-living]].<ref name="SPM2016">{{cite web|url=https://census.gov/library/publications/2016/demo/p60-258.html|title=The Supplemental Poverty Measure: 2015|author1=Renwick, Trudi|author2=Fox, Liana|date=September 13, 2016|publisher=[[United States Census Bureau]]|quote=Number and Percentage of People in Poverty by State Using 3-Year Average Over 2013, 2014, and 2015}}</ref> The SPM has been published by the Census Bureau since 2011 and expands the money income definition of poverty used by the official poverty measure.<ref>{{cite web |author1=US Census Bureau|title=Improvements to the Census Bureau&#8217;s Supplemental Poverty Measure |url=https://www.census.gov/topics/income-poverty/supplemental-poverty-measure/library/working-papers/topics/potential-changes.html |website=Census.gov |language=en}}</ref>

==See also==
* [[Norman K. Brown]], known as "Mr. Census" for having worked as an enumerator on every census from 1960 to 2020
* [[Census-designated place]] (CDP), a populated community that lacks a separate municipal government
* [[Combined statistical area]] (CSA), an area that combines adjacent μSAs and MSAs
* [[DUALabs]]
* [[List of U.S. states by historical population]], state-level U.S. census data, 1790–2020, in table form
* [[Race and ethnicity in the United States census]]
* [[State censuses in the United States of America]]
* [[United States metropolitan area]] (MSA), an area that includes adjacent communities to major cities
* [[United States micropolitan area]] (μSA), an urban area based around a core city or town with a population of 10,000 to 49,999

==Notes==
{{notelist}}

==References==
{{reflist}}

==Further reading==
* [[Margo J. Anderson|Anderson, Margo J.]] ''The American Census: A Social History''. New Haven: [[Yale University Press]], 1988. {{ISBN|0-300-04014-8}}
* Anderson, Margo J. ''The American Census: A Social History, Second Edition''. New Haven: [[Yale University Press]], 2015. {{ISBN|978-0-300-19542-2}}
* Anderson, Margo J. ''Encyclopedia of the U.S. Census''. Washington, DC: CQ Press, 2000. {{ISBN|1-56802-428-2}}.
* Dorman, Robert L. "The Creation and Destruction of the 1890 Federal Census", ''American Archivist'', 71 (Fall–Winter 2008), 350–83.
* Kruger, Stephen. "The Decennial Census" (2025). https://ssrn.com/abstract=1985554.
* Ruggles, Steven, Diana L Magnuson. 2020. "[[doi:10.1093/jahist/jaaa007|Census Technology, Politics, and Institutional Change, 1790–2020]]", ''Journal of American History'' 107(1): 19–51.
* Schor, Paul. ''Counting Americans: How the US Census Classified the Nation.'' New York: Oxford University Press, 2017.
* Lavin, Michael R. "Understanding the Census: A Guide for Marketers, Planners, Grant Writers, and Other Data Users". Kenmore, NY: Epoch Books, 1996. {{ISBN|0-89774-995-2}}.
* U.S. Department of Commerce, U.S. Census Bureau. [http://purl.access.gpo.gov/GPO/LPS19359 Measuring America: the decennial censuses from 1790 to 2000]. 2002

==External links==
{{commons}}
* [https://www.census.gov/ U.S. Census Bureau official website]
** [https://web.archive.org/web/20131001195953/http://www.census.gov/prod/www/abs/decennial/index.htm Historical Census of Population and Housing reports]
* [http://www.nhgis.org National Historical Geographic Information System], a main source for freely downloading census data for the period 1790 through the present
* [http://usa.ipums.org/usa/ Integrated Public Use Microdata Series], the main source for census [[microdata (statistics)|microdata]] for the period 1850 through the present
* [http://www.censusscope.org CensusScope], from the Social Science Data Analysis Network
* [https://web.archive.org/web/20070815235059/http://fisher.lib.virginia.edu/collections/stats/histcensus/index.html Historical U.S. Census Browser], from the University of Virginia Library
* [https://web.archive.org/web/20160308194351/http://www.censusfinder.com/census-questions.htm Census Findings – Questions Asked in Each Census Year], from CensusFinder.com.
* [http://people.howstuffworks.com/census.htm How the Census Works], from HowStuffWorks, Inc.
* [https://web.archive.org/web/20071230052358/http://libraries.mit.edu/guides/types/census/sources.html Sources of U.S. Census Data], from MIT Libraries
* [http://1890censussupplementbookset.yolasite.com/ 1890 Census Supplement Book-Set]

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{{USCensus Geography}}
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[[Category:United States census| ]]
[[Category:Recurring events established in 1790]]
[[Category:Censuses in the United States| ]]
[[Category:United States Census Bureau|Census]]