View source for Census

{{distinguish|Censer|Census (feudal tax){{!}}Censive||Censure|Senser|Sensor}}
{{Short description|Compilation of information about a given population}}

[[File:Volkstelling 1925 Census.jpg|thumb|A census taker visits a family of indigenous [[Dutch Travellers]] living in a [[mobile home|caravan]] in the [[Netherlands]] in 1925.]]
A '''census''' (from [[Latin]] ''[[wikt:censere#Latin|censere]]'', 'to assess') is the procedure of systematically acquiring, recording, and calculating information about the members of a given [[Statistical population|population]], which are then usually displayed through statistics. This term is used mostly in connection with [[Population and housing censuses by country|national population and housing censuses]]; other common censuses include [[Census of agriculture|censuses of agriculture]], traditional culture, business, supplies, and traffic censuses. The [[United Nations]] (UN) defines the essential features of population and housing censuses as "individual enumeration, universality within a defined territory, simultaneity and defined periodicity", and recommends that population censuses be taken at least every ten years. UN recommendations also cover census topics to be collected, official definitions, classifications, and other useful information to coordinate international practices.<ref>United Nations (2008). [http://unstats.un.org/unsd/demographic/sources/census/docs/P&R_Rev2.pdf Principles and Recommendations for Population and Housing Censuses] {{Webarchive|url=https://web.archive.org/web/20110514112357/http://unstats.un.org/unsd/demographic/sources/census/docs/P%26R_Rev2.pdf |date=2011-05-14 }}. Statistical Papers: Series M No. 67/Rev. 2. p. 8. {{ISBN|978-92-1-161505-0}}.</ref><ref>{{cite web|url=http://www.unece.org/fileadmin/DAM/stats/publications/CES_2010_Census_Recommendations_English.pdf |archive-url=https://web.archive.org/web/20111027034936/http://www.unece.org/fileadmin/DAM/stats/publications/CES_2010_Census_Recommendations_English.pdf |archive-date=2011-10-27 |url-status=live |title=CES 2010 Census Recommendations |website=Unece.org |access-date=2013-11-19}}</ref>

The [[United Nations|UN]]'s [[Food and Agriculture Organization]] (FAO), in turn, defines the census of agriculture as "a statistical operation for collecting, processing and disseminating data on the structure of agriculture, covering the whole or a significant part of a country." "In a census of agriculture, data are collected at the holding level."<ref name=":1">{{Cite book|url=http://www.fao.org/documents/card/en/c/506491e2-2ed4-4a7d-8104-6358d0e40adc|title=World Programme for the Census of Agriculture 2020 Volume 1: Programme, concepts and definitions|publisher=FAO|year=2015|isbn=978-92-5-108865-4|series=FAO statistical development series No. 15|location=Rome|access-date=2020-11-19|archive-date=2020-11-10|archive-url=https://web.archive.org/web/20201110154327/http://www.fao.org/documents/card/en/c/506491e2-2ed4-4a7d-8104-6358d0e40adc|url-status=live}} [[File:CC-BY icon.svg|50px]] Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/3.0/igo/ Creative Commons Attribution 3.0 IGO (CC BY 3.0 IGO)] {{Webarchive|url=https://web.archive.org/web/20191124095033/https://creativecommons.org/licenses/by/3.0/igo/ |date=2019-11-24 }} license.</ref>

The word is of [[Latin]] origin: during the [[Roman Republic]], the census was a list of all adult males fit for military service. The modern census is essential to [[international comparisons]] of any type of statistics, and censuses collect data on many attributes of a population, not just the number of individuals. Censuses typically began as the only method of collecting national [[Demography|demographic]] data and are now part of a larger system of different surveys. Although population and [[citizenship]]<ref name="e048">{{cite journal | last=Christopher | first=A. J. | title=Nationality and citizenship in the Commonwealth census record | journal=Commonwealth & Comparative Politics | volume=57 | issue=3 | date=3 July 2019 | issn=1466-2043 | doi=10.1080/14662043.2019.1563754 | pages=262–281 | url=https://www.tandfonline.com/doi/full/10.1080/14662043.2019.1563754 | access-date=27 July 2025| url-access=subscription }}</ref> estimates remain an important function of a census, including exactly the geographic distribution of the population or the agricultural population, statistics can be produced about combinations of attributes, e.g., education by age and sex in different regions. Current [[administrative data]] systems allow for other approaches to enumeration with the same level of detail but raise concerns about privacy and the possibility of biasing estimates.<ref name="theforgottenfamily.wordpress.org">{{cite web |url=https://theforgottenfamily.wordpress.com/2017/01/19/history-and-development-of-the-census-in-england-and-wales/ |title=History and Development of the Census in England and Wales |website=theforgottenfamily.wordpress.org |date=2017-01-19 |access-date=2017-01-20 |archive-date=2017-02-02 |archive-url=https://web.archive.org/web/20170202022221/https://theforgottenfamily.wordpress.com/2017/01/19/history-and-development-of-the-census-in-england-and-wales/ |url-status=live }}</ref>

A census can be contrasted with [[sampling (statistics)|sampling]] in which information is obtained only from a subset of a population; typically, main population estimates are updated by such [[intercensal estimate]]s. Modern census data are commonly used for research, business [[marketing]], and planning, and as a baseline for designing sample surveys by providing a [[sampling frame]] such as an address register. Census counts are necessary to adjust samples to be representative of a population by weighting them as is common in [[opinion poll]]ing. Similarly, [[stratified sampling|stratification]] requires knowledge of the relative sizes of different population strata, which can be derived from census enumerations. In some countries, the census provides the official counts used to apportion the number of elected representatives to regions (sometimes controversially – e.g., ''[[Utah v. Evans]]''). In many cases, a carefully chosen random sample can provide more accurate information than attempts to get a population census.<ref>Salant, Priscilla, and Don A. Dillman. "How to Conduct your Survey: Leading professional give you proven techniques for getting reliable results." (1995)</ref>
[[File:Lastcensus.svg|thumb|300px|A world map showing countries' most recent censuses as of 2020]]

==History==

=== Iran ===
One of the earliest systematic censuses in world history was conducted during the early [[Achaemenid Empire|Achaemenid period]], up until the reign of [[Darius the Great|Darius The Great]] in [[History of Iran|Ancient Iran]]. This census, aimed at [[Financial plan|financial planning]], [[military organization]], and [[Revenue service|tax collection]], spanned regions across three continents: [[Asia]], [[Africa]], and [[Europe]]. It included data on population numbers, the wealth of cities and provinces ([[Satrap|Satrapies]]), precise assessments of agricultural lands, the resources of each region, and other factors critical to determining state finances and planning for governance and military operations.<ref>{{Cite book |last1=Hackl |first1=Johannes |last2=Ruffing |first2=Kai |title=A Companion to the Achaemenid Persian Empire |chapter=Taxes and Tributes |date=2021-06-25 |pages=965–979 |doi=10.1002/9781119071860.ch67|isbn=978-1-119-17428-8 }}</ref>

===Egypt===
{{main|Census in Egypt}}

The earliest Egyptian census was the [[cattle count]], which counted not people but livestock (especially but not exclusively cows) for taxation purposes. During the early [[Old Kingdom of Egypt|Old Kingdom]] it was taken every two years; the frequency increased over time. Human censuses in Egypt first appeared in the late [[Middle Kingdom of Egypt|Middle Kingdom]] and developed in the [[New Kingdom of Egypt|New Kingdom]].<ref>D. Valbelle. "Les recensements dans l'Egypte pharaonique des troisième et deuxième millénaires" CRIPEL 9 (1987)  37 - 49.</ref> [[Herodotus]] wrote that [[Ahmose I]], first monarch of the New Kingdom, required every Egyptian to declare annually to the [[nomarch]], "whence he gained his living".<ref>Herodotus, Histories II, 177, 2</ref> Under the [[Ptolemies]] and the [[Roman Egypt|Romans]] several censuses were conducted in Egypt by government officials.<ref>Paul Cartledge, Peter Garnsey, Erich S. Gruen Hellenistic Constructs: Essays in Culture, History, and Historiography  242 ss.</ref>

===Ancient Greece===
There are several accounts of ancient Greek city states carrying out censuses.<ref>{{Cite journal |last=Missiakoulis |first=Spyros |year=2010 |title=Cecrops, King of Athens: the First (?) Recorded Population Census in History |journal=International Statistical Review |volume=78 |issue=3 |pages=413–18 |doi=10.1111/j.1751-5823.2010.00124.x |s2cid=120868478}}</ref>

===Israel===
Censuses are mentioned several times in the [[Bible|Biblical]] narrative. God commands a [[Tax per head|per capita tax]] to be paid with the census<ref>{{bibleref|Exodus|30:11–16}}</ref> for the upkeep of the [[Tabernacle]]. The [[Book of Numbers]] is named after the counting of the Israelite population<ref>{{bibleref|Numbers|1–4}}</ref> according to the house of the Fathers after the exodus from Egypt. A second census was taken while the Israelites were camped in the "[[plains of Moab]]".<ref>{{bibleref|Numbers|26}}</ref> King [[David]] performed a census that produced disastrous results.<ref>{{Bibleverse|2|Samuel|24}} and {{Bibleverse|1|Chronicles|21}}</ref> His son, King [[Solomon]], had all of the foreigners in Israel counted.<ref>{{Bibleverse|2|Chronicles|2:17}}</ref>

===China===
{{expand section|date=August 2025}}
{{main|Census in China}}
One of the world's earliest preserved censuses<ref name="Hymes">{{cite book |author=[[Robert Hymes]] |url=https://archive.org/details/columbiachronolo00john |title=Columbia Chronologies of Asian History and Culture |publisher=Columbia University Press |year=2000 |isbn=978-0-231-11004-4 |editor=John Stewart Bowman |page=[https://archive.org/details/columbiachronolo00john/page/12 12] |url-access=registration}}</ref> was held in China in AD{{nbsp}}2 during the [[Han dynasty]], and is still considered by scholars to be quite accurate.<ref name="Twitchett">Twitchett, D., Loewe, M., and Fairbank, J.K. ''Cambridge History of China: The Ch'in and Han Empires 221 B.C.–A.D. 220''. Cambridge University Press (1986), p. 240.</ref>{{sfnp|Nishijima|1986|pp=595–96}}<ref>{{cite journal |last1=Yoon |first1=H. |year=1985 |title=An early Chinese idea of a dynamic environmental cycle |journal=[[GeoJournal]] |volume=10 |issue=2 |pages=211–12 |bibcode=1985GeoJo..10..211Y |doi=10.1007/bf00150742 |s2cid=189888642}}</ref> The population was registered as having 57,671,400 individuals in 12,366,470 households but on this occasion only taxable families had been taken into account, indicating the income and the number of soldiers who could be mobilized.{{sfnp|Nishijima|1986|pp=595–96}} Another census was held in AD{{nbsp}}144.

===India===
The oldest recorded census in India is thought to have occurred around 330{{nbsp}}BC during the reign of Emperor [[Chandragupta Maurya]] under the leadership of [[Chanakya]] and [[Ashoka]].<ref>{{cite web |title=Census Commissioner of India – Historical Background |url=http://censusindia.gov.in/Data_Products/Library/Indian_perceptive_link/History_link/censushistory.htm |url-status=live |archive-url=https://web.archive.org/web/20110819100814/http://censusindia.gov.in/Data_Products/Library/Indian_perceptive_link/History_link/censushistory.htm |archive-date=2011-08-19 |access-date=2011-08-12 |publisher=Govt. of India |quote=The records of census conducted appears from 300 BC.}}</ref>

===Rome===
[[File:Meister der Kahriye-Cami-Kirche in Istanbul 005.jpg|thumb|An early 13th-century mosaic in the [[Chora Church]] depicting the [[Virgin Mary]] and [[Saint Joseph]] registering for the [[Census of Quirinius]]]]
{{see also|Roman censor|Indiction}}

The English term is taken directly from the [[Latin]] ''census'', from ''{{linktext|censere}}'' ("to estimate"). The census played a crucial role in the administration of the Roman government, as it was used to determine the class a citizen belonged to for both military and tax purposes. Beginning in the middle republic, it was usually carried out every five years.<ref>[[Walter Scheidel|Scheidel, Walter]] (2009) ''Rome and China: comparative perspectives on ancient world empires''. Oxford University Press, p. 28.</ref> It provided a register of citizens and their property from which their duties and privileges could be listed. It is said to have been instituted by the Roman king [[Servius Tullius]] in the {{nowrap|6th century BC,<ref>[[Livy]] ''[[Ab urbe condita (book)|Ab urbe condita]]'' 1.42</ref>}} at which time the number of arms-bearing citizens was supposedly counted at around 80,000.<ref>[[Livy]] ''[[Ab urbe condita (book)|Ab urbe condita]]'' 1.42, citing [[Fabius Pictor]]</ref> When the Romans conquered Judea in AD{{nbsp}}6, the legate [[Publius Sulpicius Quirinius]] organized a [[Census of Quirinius|census]] for tax purposes, which was partially responsible for the development of the [[Zealot]] movement and several failed rebellions against Rome ultimately ending in the [[Jewish Diaspora]]. The [[Gospel of Luke]] makes reference to Quirinius' census in relation to the [[birth of Jesus]];<ref>{{bibleref|Luke|2:1–2}}</ref> based on variant readings of this passage, a minority of biblical scholars, including [[N. T. Wright]], speculate that this passage refers to a separate registration conducted during the reign of [[Herod the Great]], several years before Quirinius' census.<ref>{{cite book |last=Wright |first=Nicholas |author-link=N. T. Wright |title=Who Was Jesus? |date=9 March 1993 |publisher=Wm. B. Eerdmans Publishing Co. |isbn=978-0-8028-0694-9 |pages=88–89}}</ref> The 15-year [[indiction]] cycle established by [[Diocletian]] in AD{{nbsp}}297 was based on quindecennial censuses and formed the basis for dating in late antiquity and under the [[Byzantine calendar|Byzantine Empire]].

===Rashidun and Umayyad Caliphates===
In the [[Middle Ages]], the [[Caliphate]] began conducting regular censuses soon after its formation, beginning with the one ordered by the second [[Rashidun Caliphate|Rashidun]] [[caliph]], [[Umar]].<ref>{{Cite journal |last=al-Qādī |first=Wadād |date=July 2008 |title=Population Census and Land Surveys under the Umayyads (41–132/661–750) |journal=Der Islam |volume=83 |issue=2 |pages=341–416 |doi=10.1515/ISLAM.2006.015 |s2cid=162245577}}</ref>

===Medieval Europe===
The [[Domesday Book]] was undertaken in AD{{nbsp}}1086 by [[William I of England]] so that he could properly tax the land he had recently conquered. In 1183, a census was taken of the [[crusade]]r [[Kingdom of Jerusalem]], to ascertain the number of men and amount of money that could possibly be raised against an invasion by [[Saladin]], sultan of [[Egypt]] and [[Syria]].

The first national census of France ({{Lang|fr|L'État des paroisses et des feux}}) was undertaken in 1328, mostly for fiscal purposes. It estimated the French population at 16 to 17 million.

===Inca Empire===
In the 15th century, the [[Inca Empire]] had a unique way to record census information. The Incas did not have any written language but recorded information collected during censuses and other numeric information as well as non-numeric data on [[quipus]], strings from [[llama]] or [[alpaca]] hair or cotton cords with numeric and other values encoded by knots in a [[base-10]] positional system.<ref>D'altroy, Terence N. (2001). 154</ref>

===Spanish Empire===
On May 25, 1577, [[Philip II of Spain|King Philip II of Spain]] ordered by royal cédula the preparation of a general description of Spain's holdings in the Indies. Instructions and a questionnaire, issued in 1577 by the Office of the Cronista Mayor, were distributed to local officials in the Viceroyalties of [[New Spain]] and Peru to direct the gathering of information. The questionnaire, composed of fifty items, was designed to elicit basic information about the nature of the land and the life of its peoples. The replies, known as "{{lang|es|relaciones geográficas}}", were written between 1579 and 1585 and were returned to the Cronista Mayor in Spain by the Council of the Indies.

==Sampling==
[[File:Tehran Census 1869.png|thumb|The [[Tehran]] census in 1869<ref>{{Cite web |title=Amar darolkhaneh |url=http://files.tarikhema.org/pdf/ejtemaee/Amar_darolkhaneh_Tarikhema_org.pdf |archive-url=https://web.archive.org/web/20191103114014/http://files.tarikhema.org/pdf/ejtemaee/Amar_darolkhaneh_Tarikhema_org.pdf |archive-date=2019-11-03 |url-status=live |access-date=20 November 2022 |website=tarikhema.org}}</ref>]]{{Single source|date=October 2024|section}}
A census is often construed as the opposite of a sample as it intends to count everyone in a population, rather than a fraction. However, population censuses do rely on a [[sampling frame]] to count the population. This is the only way to be sure that everyone has been included, as otherwise those not responding would not be followed up on and individuals could be missed. The fundamental premise of a census is that the population is not known, and a new estimate is to be made by the analysis of primary data. The use of a sampling frame is [[counterintuitive]] as it suggests that the [[population size]] is already known. However, a census is also used to collect attribute data on the individuals in the nation, not only to assess population size. This process of sampling marks the difference between a historical census, which was a house-to-house process or the product of an imperial decree, and the modern [[Statistics|statistical]] project.

The sampling frame used by a census is almost always an address register. Thus, it is not known if there are any residents or how many people there are in each household. Depending on the mode of enumeration, a form is sent to the householder, an enumerator calls, or administrative records for the dwelling are accessed. As a preliminary to the dispatch of forms, census workers will check for any address problems on the ground. While it may seem straightforward to use the postal service file for this purpose, this can be out of date and some dwellings may contain several independent households. A particular problem is what is termed "[[communal establishments]]", a category that includes student residences, religious orders, homes for the elderly, people in prisons, etc. As these are not easily enumerated by a single householder, they are often treated differently and visited by special teams of census workers to ensure they are classified appropriately.<ref>{{Cite web |title=Communal establishment type |url=https://www.scotlandscensus.gov.uk/metadata/communal-establishment-type/ |access-date=2024-01-10 |website=Scotland's Census |language=en}}</ref>

==Residence definitions==
Individuals are normally counted within [[household]]s, and information is typically collected about the household structure and the housing. For this reason, international documents refer to censuses of population and housing. Normally the census response is made by a household, indicating details of individuals resident there. An important aspect of census enumerations is determining which individuals can be counted and which cannot be counted. Broadly, three definitions can be used: ''de facto'' residence; ''de jure'' residence; and permanent residence. This is important in considering individuals who have multiple or temporary addresses. Every person should be identified uniquely as a resident in one place; but the place where they happen to be on census day, their [[Home range|''de facto'' residence]], may not be the best place to count them. Where an individual uses services may be more useful, and this is at their usual residence. An individual may be recorded at a "permanent" address, which might be a family home for students or long-term migrants.<ref name=":2">{{Cite web |title=Census |url=https://www.britannica.com/science/census |access-date=2024-02-05 |website=Deezer |language=en-GB}}</ref>

A precise definition of residence is needed, to decide whether visitors to a country should be included in the population count. This is becoming more important as students travel abroad for education for a period of several years. Other groups causing problems with enumeration are newborn babies, refugees, people away on holiday, people moving home around census day, and people without a fixed address.

People with second homes, because they are working in another part of the country or have a holiday cottage, are difficult to fix at a particular address; this sometimes causes double counting or houses being mistakenly identified as vacant. Another problem is where people use a different address at different times e.g. students living at their place of education in term time but returning to a family home during vacations, or children whose parents have separated who effectively have two family homes. Census enumeration has always been based on finding people where they live, as there is no systematic alternative: any list used to find people is likely to be derived from census activities in the first place. Recent [[United Nations|UN]] guidelines provide recommendations on enumerating such complex households.<ref>{{cite web |url=http://www.unece.org/emerging_forms_families_households.html |title=Measurement of emerging forms of families and households |publisher=UNECE |access-date=2012-12-12 |archive-date=2012-11-09 |archive-url=https://web.archive.org/web/20121109155201/http://www.unece.org/emerging_forms_families_households.html |url-status=live }}</ref>

In the census of [[agriculture]], data is collected at the agricultural holding unit. An agricultural holding is an economic unit of agricultural production under single management comprising all livestock kept and all land used wholly or partly for agricultural production purposes, without regard to title, legal form, or size. Single management may be exercised by an individual or household, jointly by two or more individuals or households, by a clan or tribe, or by a juridical person such as a corporation, cooperative, or government agency. The holding's land may consist of one or more parcels, located in one or more separate areas or one or more territorial or administrative divisions, providing the parcels share the same production means, such as labor, farm buildings, [[Machine|machinery]] or draught animals.<ref name=":1" />

==Enumeration strategies==
[[File:Enumerator.jpg|thumb|An enumerator conducting a census survey using a mobile phone-based questionnaire in the rural [[Mutasa District]] in [[Zimbabwe]] in 2015]]
Historical censuses used direct field enumeration and assumed that the information collected was fully accurate, with no measurement error. Modern approaches take into account the problems of overcount and undercount and the coherence of census enumerations with other official sources of data.{{clarify|date=May 2019}} For instance, during the 2020 U.S. Census, the Census Bureau counted people primarily by collecting answers sent by mail, on the internet, over the phone, or using shared information through proxies. These methods accounted for 95.5 percent of all occupied housing units in the United States.<ref>{{cite web |last1=Percival |first1=Kelly |last2=Fong |first2=Clara |title=Understanding the Census Bureau's Methods for Completing the 2020 Count |url=https://www.brennancenter.org/our-work/research-reports/understanding-census-bureaus-methods-completing-2020-count |work=Brennan Center for Justice |access-date=2024-08-26 }}</ref> This reflects a realist approach to measurement, acknowledging that under any definition of residence there is a true value of the population{{Fix|text=gobbledegook}} but this can never be measured with complete accuracy. An important aspect of the census process is to evaluate the quality of the data.<ref>{{cite web |last1=Baffour |first1=Bernard |last2=Valente |first2=Paolo |date=13 May 2008 |title=Census Quality Evaluation: considerations from an international perspective |url=https://unece.org/fileadmin/DAM/stats/documents/ece/ces/ge.41/2008/sp.4.e.pdf |url-status=live |archive-url=https://web.archive.org/web/20131008173330/https://unece.org/fileadmin/DAM/stats/documents/ece/ces/ge.41/2008/sp.4.e.pdf |archive-date=2013-10-08 |access-date=2025-02-05 |website=United Nations Economic Commission for Europe |publisher=United Nations Statistics Division}}</ref><ref>{{cite journal | last1 = Breiman | first1 = Leo | year = 1994 | title = The 1991 Census Adjustment: Undercount or Bad Data? | journal = [[Statistical Science]] | volume = 9 | issue = 4| pages = 458–75 | doi = 10.1214/ss/1177010259 | doi-access = free }}</ref>

Many countries use a post-enumeration survey to adjust the raw census counts.<ref>World Population and Housing Census Programme (2010) [http://unstats.un.org/unsd/demographic/standmeth/handbooks/Manual_PESen.pdf Post Enumeration Surveys: Operational guidelines] {{Webarchive|url=https://web.archive.org/web/20120503082524/http://unstats.un.org/unsd/demographic/standmeth/handbooks/Manual_PESen.pdf |date=2012-05-03 }}, United Nations Secretariat, Dept of Economic and Social Affairs, Statistics Division, Tech Report</ref> This works similarly to [[capture-recapture]] estimation for animal populations. Among census experts, this method is called dual system enumeration (DSE). A sample of households is visited by interviewers who record the details of the household as of census day. These data are then matched to census records, and the number of people missed can be estimated by considering the number of people who are included in one count but not the other. This allows adjustments to the count for non-response, varying between different [[demographic]] groups. An explanation using a fishing analogy can be found in "Trout, Catfish and Roach..."<ref>Benton, P. [http://www.ons.gov.uk/ons/guide-method/census/2011/the-2011-census/census-coverage-survey/trout--catfish-and-roach.pdf Trout, Catfish and Roach: The beginner's guide to census population estimates] {{Webarchive|url=https://web.archive.org/web/20120107223425/http://www.ons.gov.uk/ons/guide-method/census/2011/the-2011-census/census-coverage-survey/trout--catfish-and-roach.pdf |date=2012-01-07 }}, [[Office for National Statistics]], UK</ref> which won an award from the [[Royal Statistical Society]] for excellence in [[official statistics]] in 2011.

Triple system enumeration has been proposed as an improvement as it would allow evaluation of the statistical dependence of pairs of sources. However, as the matching process is the most difficult aspect of census estimation this has never been implemented for a national enumeration. It would also be difficult to identify three different sources that were sufficiently different to make the triple system effort worthwhile. The DSE approach has another weakness in that it assumes there is no person counted twice (over count). In ''de facto'' residence definitions this would not be a problem but in ''de jure'' definitions individuals risk being recorded on more than one form leading to double counting. A particular problem here is students who often have a term time and family address.

Several countries have used a system known as short form/long form.<ref>[http://www.ons.gov.uk/ons/guide-method/census/2011/what-is-a-census/other-methods-of-census-taking/index.html Other methods of census taking] {{Webarchive|url=https://web.archive.org/web/20120314160532/http://www.ons.gov.uk/ons/guide-method/census/2011/what-is-a-census/other-methods-of-census-taking/index.html |date=2012-03-14 }}, [[Office for National Statistics]], UK</ref> This is a [[Sampling (statistics)|sampling]] strategy that randomly chooses a proportion of people to send a more detailed questionnaire to (the long form). Everyone receives the short-form questions. This means more data are collected, but without imposing a burden on the whole population. This also reduces the burden on the statistical office. Indeed, in the UK until 2001 all residents were required to fill in the whole form but only a 10% sample was coded and analysed in detail.<ref>{{cite web |url=http://www.ons.gov.uk/ons/guide-method/census/census-2001/about-census-2001/introduction/index.html |title=Introduction to Census 2001 |publisher=Ons.gov.uk |date=2001-04-29 |access-date=2012-12-12 |archive-date=2013-01-17 |archive-url=https://web.archive.org/web/20130117043415/http://www.ons.gov.uk/ons/guide-method/census/census-2001/about-census-2001/introduction/index.html |url-status=live }}</ref> New technology means that all data are now scanned and processed. During the [[2011 Canadian census]] there was controversy about the cessation of the mandatory long-form census; the head of [[Statistics Canada]], [[Munir Sheikh]], resigned upon the federal government's decision to do so.<ref>{{cite web |author=The Canadian Press |url=http://www.680news.com/radio/680news/article/80353--text-of-munir-sheikh-s-resignation-statement |title=Text of Munir Sheikh's resignation statement |publisher=680News |date=2010-07-21 |access-date=2012-02-19 |archive-url=https://web.archive.org/web/20111219103126/http://www.680news.com/radio/680news/article/80353--text-of-munir-sheikh-s-resignation-statement |archive-date=2011-12-19 }}</ref>

The use of alternative enumeration strategies is increasing<ref>{{cite web |url=http://www.ined.fr/en/publications/pop_soc/bdd/publication/1506/ |title=[INED&#93; Population and Societies |publisher=Ined.fr |access-date=2012-02-19 |archive-date=2013-01-17 |archive-url=https://web.archive.org/web/20130117052803/http://www.ined.fr/en/publications/pop_soc/bdd/publication/1506/ |url-status=live }}</ref> but these are not as simple as many people assume and are only used in developed countries.<ref>{{cite journal |last1=Kukutai |first1=Tahu |author-link=Tahu Kukutai |year=2014 |title=Whither the census? Continuity and change in census methodologies worldwide, 1985–2014 |journal=Journal of Population Research |volume=32 |pages=3–22 |doi=10.1007/s12546-014-9139-z |s2cid=154735445}}</ref> The Netherlands has been most advanced in adopting a census using [[administrative data]]. This allows a simulated census to be conducted by linking several different administrative databases at an agreed time. Data can be matched, and an overall enumeration established allowing for discrepancies between different data sources. A validation survey is still conducted in a similar way to the post-enumeration survey employed in a traditional census.

Other countries that have a population register use this as a basis for all the census statistics needed by users. This is most common among Nordic countries but requires many distinct registers to be combined, including population, housing, employment, and education. These registers are then combined and brought up to the standard of a statistical register by comparing the data from different sources and ensuring the quality is sufficient for official statistics to be produced.<ref>{{cite web|url=http://www.unece.org/fileadmin/DAM/stats/publications/Register_based_statistics_in_Nordic_countries.pdf |archive-url=https://web.archive.org/web/20121015113925/http://www.unece.org/fileadmin/DAM/stats/publications/Register_based_statistics_in_Nordic_countries.pdf |archive-date=2012-10-15 |url-status=live |title=Register-based statistics in the Nordic countries |website=Unece.org |year=2007 |access-date=2012-12-12}}</ref>

A recent innovation is the French instigation of a rolling census program with different regions enumerated each year so that the whole country is completely enumerated every 5 to 10 years.<ref>{{Cite web|url=http://www.statistics.gov.hk/wsc/STS017-P5-S.pdf |archive-url=https://web.archive.org/web/20170224211626/http://www.statistics.gov.hk/wsc/STS017-P5-S.pdf |archive-date=2017-02-24 |url-status=live|title=The French Rolling Census: a decade of experience|last=Durr|first=Jean-Michel and François Clanché}}</ref> In Europe, in connection with the 2010 census round, many countries adopted alternative census methodologies, often based on the combination of data from registers, surveys and other sources.<ref>{{cite web |url=http://www1.unece.org/stat/platform/display/censuses/2010+Population+Census+Round |title=2010 Population Census Round – Confluence |publisher=unece.org |access-date=2012-12-12 |archive-date=2012-11-07 |archive-url=https://web.archive.org/web/20121107120442/http://www1.unece.org/stat/platform/display/censuses/2010+Population+Census+Round }}</ref>

==Technology==
Censuses have evolved in their use of technology; censuses in 2010 used many types of computing. In Brazil, handheld devices were used by enumerators to locate residences on the ground. In many countries, census returns could be made via the Internet as well as in paper form. DSE  is facilitated by computer matching techniques that can be automated, such as [[propensity score matching]]. In the UK, all census formats are scanned and stored electronically before being destroyed, replacing the need for physical archives. The record linking to perform an administrative census would not be possible without large databases being stored on computer systems.

There are sometimes problems in introducing new technology. The US census had been intended to use handheld computers, but cost escalated, and this was abandoned, with the contract being sold to Brazil. The online response has some advantages, but one of the functions of the census is to make sure everyone is counted accurately. A system that allowed people to enter their address without verification would be open to abuse. Therefore, households have to be verified on the ground, typically by an enumerator visit or post out{{clarify|date=May 2019}}. Paper forms are still necessary for those without access to the internet. It is also possible that the hidden nature{{clarify|date=May 2019}} of an administrative census means that users are not engaged with the importance of contributing their data to official statistics.

Alternatively, population estimations may be carried out remotely with [[geographic information system]] (GIS) and [[remote sensing]] technologies.<ref>
{{cite journal
 |year=2016
 |title=Population Estimation Using a 3D City Model: A Multi-Scale Country-Wide Study in the Netherlands
 |journal=PLOS ONE
 |volume=11 | issue = 6 |article-number= e0156808
 |doi=10.1371/journal.pone.0156808
 |last1=Biljecki
 |first1=F.
 |last2=Arroyo Ohori
 |first2=K.
 |last3=Ledoux
 |first3=H.
 |last4=Peters
 |first4=R.
 |last5=Stoter
 |first5=J.
 |pmid=27254151
 |pmc=4890761
|bibcode=2016PLoSO..1156808B
 |doi-access=free
 }}</ref>

==Development==
According to the [[United Nations Population Fund]] (UNFPA), "The information generated by a population and housing census – numbers of people, their distribution, their living conditions and other key data – is critical for development."<ref name="unfpa.org">{{cite web |url=http://www.unfpa.org/census |title=Census &#124; UNFPA - United Nations Population Fund |website=UNFPA.org |access-date=2016-07-20 |archive-date=2016-02-24 |archive-url=https://web.archive.org/web/20160224043936/http://www.unfpa.org/census |url-status=live }}</ref> This is because this type of data is essential for policymakers so that they know where to invest. Many countries have outdated or inaccurate data about their populations and thus have difficulty in addressing the needs of the population.

The UNFPA said:<ref name="unfpa.org"/>
<blockquote>"The unique advantage of the census is that it represents the entire statistical universe, down to the smallest geographical units, of a country or region. Planners need this information for all kinds of development work, including: assessing demographic trends; analysing socio-economic conditions;<ref>{{cite journal|doi=10.11141/ia.45.3 | issue=45 | title=Excavations in 2014 at Wade Street, Bristol - a documentary and archaeological analysis | year=2017 | journal=Internet Archaeology | last1 = Corcos | first1 = Nick | doi-access=free }}</ref> designing evidence-based poverty-reduction strategies; monitoring and evaluating the effectiveness of policies; and tracking progress toward national and internationally agreed development goals."</blockquote>

In addition to making policymakers aware of population issues, the census is also an important tool for identifying forms of social, demographic or economic exclusions, such as inequalities relating to race, ethics, and religion as well as disadvantaged groups such as those with disabilities and the poor.

An accurate census can empower local communities by providing them with the necessary information to participate in local decision-making and ensuring they are represented.

The importance of the census of agriculture for development is that it gives a snapshot of the structure of the agricultural sector in a country and, when compared with previous censuses, provides an opportunity to identify trends and structural transformations of the sector, and points towards areas for policy intervention. Census data are used as a benchmark for current statistics and their value is increased when they are employed together with other data sources.<ref name=":1" />

==Uses of data==
Early censuses in the 19th and 20th centuries collected paper documents which had to be collated by hand, so the statistical information obtained was quite basic. The government that owned the data could publish statistics on the state of the nation.<ref>Kathrin Levitan (auth.), ''A Cultural History of the British Census: Envisioning the Multitude in the Nineteenth Century'', {{ISBN|978-1-349-29824-2|978-0-230-33760-2}} Palgrave Macmillan US 2011.</ref> The results were used to measure changes in the population and apportion representation. Population estimates could be compared to those of other countries.

By the beginning of the 20th century, censuses were recording households and some indications of their employment. In some countries, census archives are released for public examination after many decades, allowing genealogists to track the ancestry of interested people. Archives provide a substantial historical record which may challenge established views. Information such as job titles and arrangements for the destitute and sick may also shed light on the historical structure of society.

Political considerations influence the census in many countries. In [[Canada]] in 2010 for example, the government under the leadership of [[Stephen Harper]] abolished the mandatory long-form census. This abolition was a response to protests from some Canadians who resented the personal questions.<ref name="Ditchburn">{{cite news|author1=Jennifer Ditchburn|title=Tories scrap mandatory long-form census|url=https://beta.theglobeandmail.com/news/politics/tories-scrap-mandatory-long-form-census/article4323276/|website=The Globe and Mail|access-date=September 23, 2017|date=June 29, 2010|archive-date=September 20, 2018|archive-url=https://web.archive.org/web/20180920010502/https://beta.theglobeandmail.com/news/politics/tories-scrap-mandatory-long-form-census/article4323276/|url-status=live}}</ref> The long-form census was reinstated by the [[Justin Trudeau]] government in 2016.

===Research===
As governments assumed responsibility for schooling and welfare, large government [[research]] departments made extensive use of census data. Population projections could be made, to help plan for provision in local government and regions. Central government could also use census data to allocate funding. Even in the mid 20th century, census data was only directly accessible to large government departments. However, computers meant that tabulations could be used directly by university researchers, large businesses and local government offices. They could use the detail of the data to answer new questions and add to local and specialist knowledge.<ref name=":2" />

Nowadays, census data are published in a wide variety of formats to be accessible to business, all levels of government, media, students and teachers, charities, and any citizen who is interested; researchers in particular have an interest in the role of Census Field Officers (CFO) and their assistants.<ref>{{cite book|last1=Morphy|first1=Frances|title=Agency, Contingency and Census Process: Observations of the 2006 Indigenous Enumeration Strategy in Remote Aboriginal Australia|year=2007|url=https://books.google.com/books?id=Ydj3AQAAQBAJ&q=researcher%20census%20field%20officer&pg=PR11|publisher=ANU E Press|isbn=978-1-921313-58-5|access-date=19 July 2016|quote=One researcher spent time observing... the training of Census Field Officers (CFO) and their assistants....|archive-date=20 January 2023|archive-url=https://web.archive.org/web/20230120131341/https://books.google.com/books?id=Ydj3AQAAQBAJ&q=researcher%20census%20field%20officer&pg=PR11|url-status=live}}</ref> Data can be represented visually or analysed in complex statistical models, to show the difference between certain areas, or to understand the association between different personal characteristics. Census data offer a unique insight into small areas and small demographic groups which sample data would be unable to capture with precision.

In the census of agriculture, users need census data to:

# support and contribute to evidence-based agricultural planning and policy-making. The census information is essential, for example, to monitor the performance of a policy or programme designed for crop diversification or to address food security issues;
# provide data to facilitate research, investment and business decisions both in the public and private sector;
# contribute to monitoring environmental changes and evaluating the impact of agricultural practices on the environment such as tillage practices, crop rotation or sources of greenhouse gas (GHG) emissions;
# provide relevant data on work inputs and main work activities, as well as on the labour force in the agriculture sector;
# provide an important information base for monitoring some key indicators of the [[Sustainable Development Goals]] (SDGs), in particular those goals related to food security in agricultural holdings, the role of women in agricultural activities and rural poverty;
# provide baseline data both at the national and small administrative and geographical levels for formulating, monitoring and evaluating programmes and projects interventions;
# provide essential information on [[subsistence agriculture]] and for the estimation of the non-observed economy, which plays an important role in the compilation of the national accounts and the economic accounts for agriculture.<ref name=":1" />

==Privacy and data stewardship==
Although the census provides useful statistical information about a population, the availability of this information could sometimes lead to abuses, political or otherwise, by the linking of individuals' identities to anonymous census data.<ref>{{cite web |url=http://www.epic.org/privacy/census/ |title=The Census and Privacy |website=EPIC.org |access-date=2016-07-20 |archive-date=2016-06-13 |archive-url=https://web.archive.org/web/20160613025224/https://epic.org/privacy/census/ |url-status=live }}</ref> This is particularly important when individuals' census responses are made available in [[Microdata (statistics)|microdata]] form, but even aggregate-level data can result in privacy breaches when dealing with small areas and/or rare subpopulations.

For instance, when reporting data from a large city, it might be appropriate to give the average income for black males aged between 50 and 60. However, doing this for a town that only has two black males in this age group would be a breach of privacy because either of those persons, knowing his own income and the reported average, could determine the other man's income.

Typically, census data are processed to obscure such individual information. Some agencies do this by intentionally introducing small statistical errors to prevent the identification of individuals in marginal populations;<ref>{{cite web |url=http://www.abs.gov.au/websitedbs/D3110129.NSF/f61552cc746715bcca256eb000015277/2878e9589dd56b53ca257153007fe1f5!OpenDocument |title=Managing Confidentiality and Learning about SEIFA |publisher=Australian Bureau of Statistics |date=2006-04-18 |access-date=2010-11-30 |archive-date=2011-05-24 |archive-url=https://web.archive.org/web/20110524225948/http://www.abs.gov.au/websitedbs/D3110129.NSF/f61552cc746715bcca256eb000015277/2878e9589dd56b53ca257153007fe1f5!OpenDocument |url-status=live }}</ref> others swap variables for similar respondents. Whatever is done to reduce the privacy risk, new improved electronic analysis of data can threaten to reveal sensitive individual information. This is known as [[statistical disclosure control]].

Another possibility is to present survey results by means of statistical models in the form of a multivariate distribution mixture.<ref>{{cite web |url=http://www.jos.nu/Articles/abstract.asp?article=264673 |title=Statistical Model of the 2001 Czech Census for Interactive Presentation |vauthors=Grim J, Hora J, Somol P, Boček P, Pudil, P |year=2010 |work=Journal of Official Statistics, vol. 26, no. 4 |pages=673–94 |access-date=2011-01-07 |archive-date=2011-07-24 |archive-url=https://web.archive.org/web/20110724190636/http://www.jos.nu/Articles/abstract.asp?article=264673 }}</ref> The statistical information in the form of [[Conditional probability distribution|conditional distributions]] ([[histogram]]s) can be derived interactively from the estimated [[Mixture distribution|mixture model]] without any further access to the original database. As the final product does not contain any protected microdata, the model-based interactive software can be distributed without any confidentiality concerns.

Another method is simply to release no data at all, except very large scale data directly to the central government. Differing release strategies of governments have led to an international project ([[IPUMS]]) to co-ordinate access to microdata and corresponding metadata. Such projects such as [[SDMX]] also promote standardising metadata, so that best use can be made of the minimal data available.

==Boycotts==
Censuses have sometimes been the subject of threatened or realized boycotts. Political historian Laurence Cooley categorizes census boycotts into those 'motivated by concerns specifically related to the census itself' and those where 'the rationale for boycotting is not to influence the questionnaire design or the enumeration process, but rather in pursuit of aims that are incidental to the census'.<ref name="a362">{{cite journal | last=Cooley | first=Laurence | title='No status – no census!' The causes and consequences of the 1971 and 1981 Northern Ireland census boycotts | journal=Contemporary British History | volume=39 | issue=1 | date=2025-01-02 | issn=1361-9462 | doi=10.1080/13619462.2024.2387584 | doi-access=free | pages=105–142}}</ref> Boycotts of the first kind include Kenya in 2009, when some ethnic groups threatened to boycott the census if they were not allocated their own categories,<ref name="t454">{{cite journal | last=Balaton-Chrimes | first=Samantha | title=Counting as Citizens: Recognition of the Nubians in the 2009 Kenyan Census | journal=Ethnopolitics | volume=10 | issue=2 | date=2011 | issn=1744-9057 | doi=10.1080/17449057.2011.570983 | pages=205–218 | url=http://www.tandfonline.com/doi/abs/10.1080/17449057.2011.570983 | access-date=2025-05-20| url-access=subscription }}</ref> and Myanmar in 2014, when nationalists threatened a boycott if the Rohingya were allowed to self-identify.<ref name="a362"/> Examples of boycotts where the census was more of a symbolic target include the 1911 UK census, which suffrage organizations boycotted to protest against women's lack of voting rights, using the slogan 'no vote, no census'.<ref name="x735">{{cite journal | last1=Liddington | first1=J. | last2=Crawford | first2=E. | title='Women do not count, neither shall they be counted': Suffrage, Citizenship and the Battle for the 1911 Census | journal=History Workshop Journal | volume=71 | issue=1 | date=2011-03-01 | issn=1363-3554 | doi=10.1093/hwj/dbq064 | pages=98–127 | url=https://academic.oup.com/hwj/article-lookup/doi/10.1093/hwj/dbq064 | access-date=2025-05-20| url-access=subscription }}</ref> Other prominent cases of census boycotts include West Germany in 1983 and 1987.<ref name="u962">{{cite journal | last=Hannah | first=Matthew G. | title=Calculable territory and the West German census boycott movements of the 1980s | journal=Political Geography | volume=28 | issue=1 | date=2009 | doi=10.1016/j.polgeo.2008.12.001 | pages=66–75 | url=https://linkinghub.elsevier.com/retrieve/pii/S0962629809000055 | access-date=20 May 2025| url-access=subscription }}</ref>

== World population estimates ==
{{further|Estimates of historical world population}}
The earliest [[world population]] estimate of the world population was made by [[Giovanni Battista Riccioli]] in 1661; the next by [[Johann Peter Süssmilch]] in 1741, revised in 1762; the third by [[Karl Friedrich Wilhelm Dieterici]] in 1859.<ref>{{Cite journal|last=Willcox|first=Walter|date=1931|title=International Migrations, Volume II: Interpretations|url=https://www.nber.org/chapters/c5103.pdf |archive-url=https://web.archive.org/web/20160425122720/http://www.nber.org/chapters/c5103.pdf |archive-date=2016-04-25 |url-status=live|journal=NBER|volume=78 |issue=3 |page=309 |doi=10.2307/1784930 |jstor=1784930 |bibcode=1931GeogJ..78..309C }}</ref>

In 1931, Walter Willcox published a table in his book, ''International Migrations: Volume II Interpretations'', that estimated the 1929 world population to be roughly 1.8 billion.

[[File:1929 world population estimate.png|center|thumb|300px|The [[League of Nations]] and [[International Statistical Institute]] estimates of the world population in 1929]]

==Impact of COVID-19==
[[File:A Philippine Statistics Authority (PSA) enumerator interviews a resident of Molino Homes II Subdivision.jpg|thumb|A census taker interviews a resident of [[Dasmariñas]], [[Philippines]], in October 2020.]]
===Impact===
The UNFPA had predicted that the [[COVID-19 pandemic]] would threaten the successful conduct of censuses of population and housing in many countries through delays and interruptions leading to compromises in quality, or complete cancellation of census projects. Domestic and donor financing for censuses was diverted to address COVID-19 leaving censuses without crucial funds. Several countries chose to postpone their censuses as the UNFPA had recommended.<ref name=":0">{{Cite book|url=https://www.unfpa.org/sites/default/files/resource-pdf/Census_COVID19_digital.pdf |archive-url=https://web.archive.org/web/20200605123659/https://www.unfpa.org/sites/default/files/resource-pdf/Census_COVID19_digital.pdf |archive-date=2020-06-05 |url-status=live|title=Technical Brief on the Implications of COVID-19 on Census|publisher=UNFPA|year=2020}}</ref>

The pandemic also affected the planning and implementation of censuses of agriculture across the world. The extent of the impact varied according to what stage the censuses were at, ranging from planning (i.e. staffing, procurement, preparation of frames, questionnaires), fieldwork (field training and enumeration) or data processing/analysis stages. The census of agriculture's reference period is the agricultural year. Thus, a delay in any census activity proves critical and can result in a full year postponement of the enumeration if the agricultural season is missed.<ref>{{Cite book|url=https://unstats.un.org/unsd/ccsa/documents/covid19-report-ccsa_vol2.pdf |archive-url=https://web.archive.org/web/20200921071940/https://unstats.un.org/unsd/ccsa/documents/covid19-report-ccsa_vol2.pdf |archive-date=2020-09-21 |url-status=live|title=How Covid-19 is changing the world: a statistical perspective, Volume II|publisher=Committee for the Coordination of Statistical Activities (CCSA)|year=2020|chapter=Impact on censuses of agriculture and some mitigation measures (2020)}}</ref><ref>{{Cite book|title=Impact of COVID-19 on national censuses of agriculture (Status overview)|publisher=FAO|year=2020|isbn=978-92-5-132604-6|location=Rome|doi=10.4060/ca8984en|s2cid=242865907}}</ref><ref>{{Cite book|title=National agricultural census operations and COVID-19|publisher=FAO|year=2020|isbn=978-92-5-132402-8|location=Rome|doi=10.4060/ca8605en|s2cid=240817441}}</ref><ref>{{Cite journal|last=Castano|first=Jairo|date=2020|title=Censuses of agriculture and COVID-19: Global situation and lessons|journal=Statistical Journal of the IAOS|publisher=IOS Press|volume=36|issue=4|pages=861–865|doi=10.3233/SJI-200752|s2cid=229200096|doi-access=free}}</ref>

===Adaptation===
The UNFPA requested a global effort to assure that even where a census was delayed, census planning and preparations were not cancelled, but continued in order to assure that implementation could proceed safely once the pandemic was under control. While new census methods, including online, register-based, and hybrid approaches were being used across the world, these demanded extensive planning and preconditions that could not be created at short notice. The low supply of [[personal protective equipment]] to protect against COVID-19 had immediate implications for conducting censuses in communities at risk of transmission. The UNFPA Procurement Office partnered with national agencies to explore new [[supply chain]]s and resources.<ref name=":0" />

==Modern implementation==
{{main|Population and housing censuses by country}}
In the 2020 round of censuses, covering the period 2015–2024, 204 countries or areas conducted at least one census. To a greater extent than in previous years, censuses were delayed or not completed in areas that hosted a significant percentage of the global population. This was driven by factors including the [[COVID-19 pandemic]], declines in international funding for census activities, and declining trust in data collection and institutions.<ref>{{Cite journal |last1=Espey |first1=Jessica M. |last2=Tatem |first2=Andrew J. |last3=Thomson |first3=Dana R. |date=2025-06-19 |title=Disappearing people: A global demographic data crisis threatens public policy |url=https://www.science.org/doi/10.1126/science.adx8683 |journal=Science |volume=388 |issue=6753 |pages=1277–1280 |doi=10.1126/science.adx8683|pmid=40536961 |bibcode=2025Sci...388.1277E |url-access=subscription }}</ref>

==See also==
* [[List of national and international statistical services]]
* {{annotated link|Languages in censuses}}
* {{annotated link|Liber Censuum|''Liber Censuum''}}
* {{annotated link|Race and ethnicity in censuses}}
* {{annotated link|Social research}}

== Sources ==
{{Free-content attribution
| title = World Programme for the Census of Agriculture 2020 Volume 1 – Programme, concepts and definitions
| author = FAO
| publisher = FAO
| page numbers =
| source =
| documentURL = http://www.fao.org/documents/card/en/c/506491e2-2ed4-4a7d-8104-6358d0e40adc
| license statement URL = https://commons.wikimedia.org/wiki/File:World_Programme_for_the_Census_of_Agriculture_2020_Volume_1%E2%80%93_Programme,_concepts_and_definitions.pdf
| license = CC BY-SA 3.0 IGO
}}

{{Free-content attribution
| title = National agricultural census operations and COVID-19
| author = FAO
| publisher = FAO
| page numbers =
| source =
| documentURL = https://doi.org/10.4060/ca8605en
| license statement URL = https://commons.wikimedia.org/wiki/File:National_agricultural_census_operations_and_COVID-19.pdf
| license = CC BY-SA 3.0 IGO
}}

{{Free-content attribution
| title = Impact of COVID-19 on national censuses of agriculture (Status overview) (2020)
| author = FAO
| publisher = FAO
| page numbers =
| source =
| documentURL = https://doi.org/10.4060/ca8984en
| license statement URL = https://commons.wikimedia.org/wiki/File:Impact_of_COVID-19_on_national_censuses_of_agriculture_(Status_overview)_(2020).pdf
| license = CC BY-SA 3.0 IGO
}}

==Notes==
{{Reflist|30em}}

==References==
* Alterman, Hyman, (1969). ''Counting People: The Census in History''. Harcourt, Brace & Company. {{ISBN?}}
* Behrisch, Lars. (2016) "Statistics and Politics in the 18th Century", ''Historical Social Research/Historische Sozialforschung'' (2016): 238–57.
* Bielenstein, Hans, (1978). "Wang Mang, the restoration of the Han dynasty, and Later Han", in ''The Cambridge History of China'', vol. 1, eds. Denis Twitchett and John K. Fairbank, pp.&nbsp;223–90, Cambridge: Cambridge University Press.
* Krüger, Stephen, (Fall 1991). "The Decennial Census", [http://wsulawreview.org/Volume19Articles.pdf 19 ''Western State University Law Review'' 1]; available at [http://heinonline.org/HOL/LandingPage?collection=journals&handle=hein.journals/wsulr19&div=6&id=&page= HeinOnline] {{subscription required}}.
* [http://www.statistics.gov.uk/cci/nugget.asp?id=297 Effects of UK 'Jedi' hoax on 2001 UK census from ONS].
* [https://web.archive.org/web/20040214151945/http://www.census.gov/Press-Release/www/releases/archives/miscellaneous/000507.html U.S. Census Press Release on 1930 Census].
* [https://web.archive.org/web/20050227224505/http://www.archives.gov/publications/prologue/spring_2002_soundex_projects.html U.S. Census Press Release on Soundex and WPA].
* {{citation
  | surname = Nishijima | given = Sadao
  | chapter = The economic and social history of Former Han
  | pages = 545–607
  | title = Cambridge History of China: Volume I: the Ch'in and Han Empires, 221 B.C. – A.D. 220
  | editor-given1 = Denis | editor-surname1 = Twitchett
  | editor-given2 = Michael | editor-surname2 = Loewe
  | location = Cambridge | publisher = Cambridge University Press
  | year = 1986
  | isbn = 978-0-521-24327-8
  | postscript = .
  }}

==External links==
{{Commons category|Census}}
* {{cite EB1911|wstitle=Census |volume=5 |short=x}}
* [http://www.census.nationalarchives.ie/ Census of Ireland 1911].
* [https://web.archive.org/web/20160507023856/http://www.histpop.org/ Online Historical Population Reports Project (OHPR)].
* [http://www.tesionline.com/intl/thesis.jsp?idt=8384 PR as a function of census management: comparative analysis of fifteen census experiences]

{{Statistics|applications}}
{{Social surveys}}

{{Authority control}}

[[Category:Censuses| ]]
[[Category:Population]]
[[Category:Survey methodology]]
[[Category:Sampling (statistics)]]
[[Category:Latin words and phrases]]