A census is the procedure of systematically acquiring and recording information about the members of a given population. It is a regularly occurring and official count of a particular population. The term is used mostly in connection with national population and housing censuses; other common censuses include agriculture, business, and traffic censuses. In the latter cases the elements of the 'population' are farms, businesses, and so forth, rather than people. The United Nations 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 10 years. The term itself comes from Latin: during the Roman Republic the census was a list that kept track of all adult males fit for military service.

The census can be contrasted with sampling in which information is obtained only from a subset of a population, sometimes as an Intercensal estimate. Census data is commonly used for research, business marketing, and planning, as well as a baseline for sampling surveys. In some countries, census data are used to apportion electoral representation (sometimes controversially – e.g., Utah v. Evans).

Privacy

Although the census provides a useful way of obtaining statistical information about a population, such information can sometimes lead to abuses, political or otherwise, made possible by the linking of individuals' identities to anonymous census data. This consideration is particularly important when individuals' census responses are made available in 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; others swap variables for similar respondents. Whatever measures have been taken to reduce the privacy risk in census data, new technology in the form of better electronic analysis of data poses increasing challenges to the protection of sensitive individual information.

Another possibility is to present survey results by means of statistical models in the form of a multivariate distribution mixture. The statistical information in the form of conditional distributions (histograms) can be derived interactively from the estimated 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.

Historical examples

Egypt

Censuses in Egypt are said to have been taken during the early Pharaonic period in 3340 BC and in 3056 BC.

Ancient Israel

Censuses are mentioned in the Bible. God commands a flat tax to be paid with the census in for the upkeep of the Tabernacle. The Book of Numbers is named after the counting of the Israelite population (in ) according to the house of the Fathers after the exodus from Egypt. A second census was taken while the Israelite were camped in the plains of Moab, in .

King David performed a census that produced disastrous results (in and ). God used Satan to try King David (; ), who then numbered the people out of pride. His son, King Solomon, had all of the foreigners in Israel counted in .

The Gospel of Luke records Jesus being born during a census in .

China

The world's oldest surviving census data comes from China. According to The Canadian Encyclopedia, China was the first to have a recorded census over 4000 years ago. Another census comes from the Han Dynasty, in what is perhaps China's most well-known ancient census. Taken in the fall of 2 AD, it is considered by scholars to be quite accurate. By that time, there were 57.67 million people registered in 12.36 million households living in China. A third recorded census dates back to 144 AD, when 49.73 million people living in 9.94 million households were counted.

India

The oldest recorded census in India is thought to have occurred around 300 BCE during the reign of the Emperor Chandragupta Maurya under the leadership of "India's Machiavelli", Kautilya or Chanakya. The next known record comes from the reign of Akbar the enlightened Mughal Emperor of India.

Rome

The word "census" originated in ancient Rome from the Latin word ("to estimate"). The census played a crucial role in the administration of the Roman Empire, as it was used to determine taxes. With few interruptions, it was usually carried out every five years. 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 6th century BC, at which time the number of arms-bearing citizens was counted at around 80,000.

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 caliph, Umar.

Medieval Europe

The Domesday Book was undertaken in 1086 by William I of England so that he could properly tax the land he had recently conquered in medieval Europe. In 1183, a census was taken of the crusader 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.

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.

Spanish empire

On May 25, 1577, 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-Cosmógrafo, 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 "relaciones geográficas," were written between 1579 and 1585 and were returned to the Cronista Mayor-Cosmógrafo in Spain by the Council of the Indies.

Modern implementation

Afghanistan

A partial and incomplete population census was taken in Afghanistan in 1980. A census was planned for 2007.

Albania

The latest population census was conducted in Albania in April 2001. Prior to that, a census was conducted in 1989 at the end of the communist regime.

Algeria

Population and housing censuses have been carried out in Algeria in 1967, 1977, 1987, 1998, and 2008. The next census is scheduled for 2016.

Antigua and Barbuda

A Population & Housing Census was carried out in 2001. The next census is scheduled for 2011.

Argentina

National population census are carried out in Argentina roughly every ten years, the last one being performed on October 27, 2010.

Australia

The Australian census is operated by the Australian Bureau of Statistics. It is currently conducted every five years, the last occurrence being on 9 August 2011. Past Australian censuses were conducted in 1911, 1921, 1933, 1947, 1954, and 1961 - 2011 every five years. In 2006, for the first time, Australians were able to complete their census online.

Austria

The Austrian census is run by the statistics of Austria. It is carried out every ten years, the last one being 9 August 2011.

Azerbaijan

Population censuses have been taken in Azerbaijan under Russian/Soviet rule in 1897, 1926, 1937, 1939, 1959, 1970, 1979, and 1989. Beginning in 1991, two more census have been carried out in Azerbaijan: one in 1999 and one in 2009.

Bangladesh

Population censuses were conducted by the Bangladesh Bureau of Statistics (BBS) in 1974, 1981, 1991 and 2001. The 2011 Census was held from 15 to 19 March.

Barbados

Censuses on population sizes in Barbados are conducted by the Barbados Statistical Service (BSS). The last major census was conducted in 2010.

Benin

Population censuses have been taken in Benin in 1978, 1992 and 2002.

Bolivia

Population and housing censuses have been carried out in Bolivia in 1992 and 2001. The next is planned for 2012.

Brazil

The Brazilian census is carried out by the Brazilian Institute of Geography and Statistics every 10 years. The last one was in 2010. Earlier censuses were taken in 1872 (the first), 1900, 1920, 1941, 1950, 1960, 1970, 1980, 1991, 2000 and 2010.

Brazil's Demographic Census is one of the most hierarchical collection of census data in the world. Its hierarchies include: Brazil (Country), Major Regions, States, Macro-regions, micro-regions, municipalities, districts, sub-districts, Neighborhoods and census tracts.

Depending on the administrative hierarchy, some types of data are not published to respect confidentiality.

For example:

1. The lower area of data collection is the census tract, with approximately 300 households, and information is collected on age, condition of the home, gender, income, among others.

2. Districts: information on race, color, religion, disability, etc.

3. Municipalities (cities): in addition to the information already described, there is information of GDP, industrial production, agricultural production, migration between cities to study or work, to live migration, inflation, employment rates, number of industries, the quantity of trade, etc. Information is collected with handheld computers equipped with GPS receivers and digitized maps.

For more information, see the Brazilian Institute of Geography and Statistics (IBGE).

Bulgaria

Bulgarian governors organized a national census soon after the liberation of the Bulgarian lands. In 1881 a census took place in the Principality, while in 1884 a census was organized in Eastern Rumelia. The first census covering the unified state took place in 1888.

Since these first accounts, Bulgarian authorities had organized several population censuses: 1892, 1900, 1905, 1910, 1920, 1926, 1934, 1946, 1956, 1965, 1975, 1985, 1992 and 2001.

The data provided in the Bulgarian censuses from 1888 until World War II is regarded as highly reliable according to the standards of the time. The Bulgarian leading statisticians of the period were generally educated in Western universities and participated vividly in the international cooperation, therefore insisted and succeeded in introducing the best practices of the time. The quality of the data provided of later censuses is a matter of debate. The religion question in the 2001 census didn't allow the unaffiliated Bulgarians to be counted as such.

Canada

The Canadian census is run by Statistics Canada. The 1666 census of New France was conducted by French intendant Jean Talon, when he took a census to ascertain the number of people living in New France. The method and data was later used when Canada was founded 201 years later. The individual provinces (sometimes in conjunction with each other) conducted censuses in the 19th century and before. In 1871, Canada's first formal census was conducted, which counted the population of Nova Scotia, Ontario, New Brunswick, and Quebec.

Censuses in Canada are conducted in five-year intervals. The last census was conducted in 2011. Censuses taken in mid-decade (1976, 1986, 1996, etc.) are referred to as quinquennial censuses. Others are referred to as decennial censuses. The first quinquennial census was conducted in 1956.

For the 2006 Census of Canada, respondents were able, for the first time, to choose to complete their census questionnaire online. Other options for answering the questionnaire include postal mail (using a pre-paid envelope) and telephone (using an 800 number).

In the Province of Alberta, Section 57 of its Municipal Government Act (MGA) enables municipalities to perform their own censuses on any given year.

Chile

National population censuses are carried out in Chile every ten years by the INE (Instituto Nacional de Estadísticas, or National Statistics Institute), the last one being in 2002.

China

Population censuses have been taken in the Republic and People's Republic of China in 1913, 1944, 1953, 1964, 1982, 1990, 2000, and 2010. These were the world's biggest censuses as they attempted to count every man, woman and child in the most populous nation in the world. Some 6 million enumerators were engaged in the 2000 and 2010 censuses.

Between National Population Censuses, 1% National Population Sample Surveys were taken in 1987, 1995, 2005 and 0.1% National Population Sample Surveys have been taken annually since 2000.

National agricultural, economic, and industrial censuses are also taken on a regular basis. The first economic census was taken in 2004 and the second 2008.

Costa Rica

Costa Rica carried out its tenth population census in 2011. INEC, National Institute of Statistics and Census is in charge of conduct these censuses. Past Costa Rican censuses were conducted in 1864, 1883, 1892, 1927, 1950, 1963, 1973, 1984, and 2000.

Croatia

The census in Croatia is carried out every 10 years. The last census was taken in 2011 (from April 1 to April 28). The first census was in 1857 when what is now Croatia was part of Austrian Empire.

Czech Republic

The census in the Czech Republic is carried out every 10 years by the Czech Statistical Office. The last census was taken in 2011. Earlier censuses were taken in 1869, 1880, 1890, 1900, 1910, 1921, 1930, 1950, 1961, 1970, 1980, 1991 and 2001.

The results of the last census are also available via the interactive model based software.

Denmark

The first Danish census was in 1700-1701, and contained statistical information about adult men. Only about half of it still exists. A census of school children was taken during the 1730s.

Following these early undertakings, the first census to attempt completely covering all citizens (including women and children who had previously been listed only as numbers) of Denmark-Norway was taken in 1769. At that point there were 797,584 citizens in the kingdom. Georg Christian Oeder took a statistical census in 1771 which covered Copenhagen, Sjælland, Møn, and Bornholm.

After that, censuses followed somewhat regularly in 1787, 1801, and 1834, and between 1840 and 1860, the censuses were taken every five years, and then every ten years until 1890. Special censuses for Copenhagen were taken in 1885 and 1895.

In the 20th century, censuses were taken every five years from 1901 to 1921, and then every ten years from 1930. The last traditional census was taken in 1970.

A limited population census based on registers was taken in 1976. From 1981 and each year onwards information that corresponds to a population and housing census is retrieved from registers. Denmark was the first country in the world to conduct these censuses from administrative registers. The most important registers are the Population Register (Det Centrale Personregister), the Building and Dwelling Register and the Enterprise Register. The central statistical office, Statistics Denmark is responsible for compiling these data. This information is available online in the Statbank Denmark.

It is possible to search a portion of the Danish censuses online at the Dansk Demografisk Database, and also view scanned versions at Arkivalier Online.

Egypt

The Statistical Department of the Ministry of Finance conducted the first census in 1882, which considered as a preparatory step; the first true population census was conducted in 1897. Thereafter, censuses were conducted at ten-year intervals in 1907, 1917, 1927 and so on.

Estonia

Population censuses have been taken in Estonia in 1881, 1897, 1922, 1934, 1959, 1970, 1979, 1989 and 2000, and is being taken in January 2012. The responsible institution is the Statistics Estonia.

Ethiopia

Three censuses have been taken in Ethiopia: 1984, 1994 and in 2007. The responsible institution is the Central Statistical Agency.

Most of the census in 2007 was taken in August, while the Somali Region and the Afar Region were not covered. The northern Afar region is a remote, hot and arid area. The eastern Somali region (Ogaden) hosts a large nomadic Somali population and is a conflict area where Ethiopian regular forces are fighting against Ogaden National Liberation Front (ONLF).

Finland

The first population census was taken in 1749 when Finland was a part of Sweden. The most recent census took place on December 31, 2000.

France

The census in France is carried out by INSEE. Since 2004, a partial census is carried out every year, and the results published as averages over 5 years.

Germany

The first systematic population on the European continent was taken in 1719 in Prussia (roughly corresponding to today's northern Germany and western Poland).

The first large-scale census in the German Empire took place in 1895. Attempts at introducing a census in West Germany sparked strong popular resentment in the 1980s since many quite personal questions were asked. Some campaigned for a boycott. In the end the Constitutional Court stopped the census in 1980 and 1983. The last census was in 1987. Germany has since used population samples in combination with statistical methods, in place of a full census.

Greece

Census takes place every 10 years and is carried out by the National Statistical Service of Greece. A 2011 is taking place right now and will end in the 24th of May. Last census was in 2001.

Guatemala

Modern population censuses have been taken in Guatemala in 1930, 1950, 1964, 1973, 1981, 1994 and in 2002. Controversial cenuses include those in 1950 and 1964 (misclassification of the Maya population) and 1994 (generally questioned). About 14,000,000 people live in Guatemala as of July 2009.

Hong Kong

Census takes place every 10 years and by-census between two censuses by the Census and Statistics Department of Hong Kong. The last census was conducted in 2001 and the next census would be taken in 2011.

Hungary

Official decennial censuses have been taken in Hungary since 1870; the latest one – in line with the recommendations of the United Nations and the Statistical Office of the European Union – was carried out in 2001. Starting from 1880 the Hungarian census system was based on native language (the language spoken at home in the early life of the person and at the time of the survey), vulgar language (the most frequently used language in the family), and other spoken languages.

Iceland

The first Icelandic census took place in 1703, following upon the first Danish census of 1700–1701. Further censuses were carried out in 1801, 1845 and 1865. The 1703 exercise was the first ever census to cover all inhabitants of an entire country, mentioning the name, age and social position of each individual. All of the information still exists, although some of the original documents have been lost.

The setting up, in 1952, of the National Registry (Þjóðskrá) eliminated the need for censuses. All those born in Iceland, and all new residents, are automatically registered. Individuals are identified in the registry by means of a national identification number (the so-called kennitala), a number composed of the date of birth in the format ddmmyy and four additional digits, the third of which is a control digit, and the last of which indicates the century in which the person was born (9 for the 1900s and 0 for the 2000s).

The National Registry doubles as an electoral register. Likewise, all bank accounts are linked to the national identification of the owner (companies and institutions all have their own identification numbers).

=== India === The decennial census of India is the primary source of information about the demographic characteristics of the population of India. The 2011 census will be one of the largest censuses in the history of mankind.

The first census in India in modern times was conducted in 1872. First regular census was started in 1881 by Lord Rippon.Since then, a population census has been carried out every 10 years. The latest census commenced on 1 May 2010. It will create a National Population Register with photographs and fingerprints of every resident. All usual residents of India will also be provided with their Unique ID numbers and National Identity Cards. The census is carried out by the office of the Register General and Census Commissioner of India, Delhi, an office in the Ministry of Home Affairs, Government of India, under the 1948 Census of India Act. The act gives Central Government many powers like to notify a date for Census, power to ask for the services of any citizen for census work. The law makes it compulsory for every citizen to answer the census questions truthfully. The Act provides penalties for giving false answers or not giving answers at all to the census questionnaire. One of the most important provisions of law is the guarantee for the maintenance of secrecy of the information collected at the census of each individual. The census records are not open to inspection and also not admissible in evidence.

The census is conducted in two phases: first, house listing and house numbering phase and second, the actual population enumeration phase. The census is carried out by the canvassing method. In this method, each and every household is visited and the information is collected by specially trained enumerator. They collect data related to households e.g. number of members, water & electricity supply, ownership of land, vehicles, computers and other assets and services. In the second phase, total population is counted and statistics related to individuals are collected.

Indonesia

The first population census was done during the colonial era, 1930. Before that, a non-overall census was already conducted in 1920. After that census was done irregularly. The first census after independence was 1961, followed by 1971. Since 1980 it is conducted regularly every 10 years. In between, there is also economical census (every 10 years, five years after population census) and agricultural census (three years after population census).The last census was held on May 2010.

Iran

Main article: Demographics of Iran

The Statistical Center of Iran carried out nationwide population and housing censuses every 10 years, the last of which occurred in 2006 (1385 AP). In the Islamic Republic of Iran, based on Article 4 of the Act of the Statistical Center of Iran (SCI), the census shall be implemented once every 10 years according to the Presidential decree. So far there have been 6 incidences of population census in Iran in the years 1956, 1966, 1976, 1986, 1996, and 2006; all taken in accordance with scientific methods. Since 2008 census in iran carries out every 5 year.

Ireland

The census in Ireland is carried out by the Central Statistics Office. The census is carried out every five years, with more detailed information collected in years ending in 1 and less in the years ending in 6. The 1976 census was canceled as a cost-saving measure, but a supplementary census was held in 1979 after it became apparent that the 1970s had seen major demographic changes. The census scheduled for 2001 was postponed until 2002 due to the outbreak of foot-and-mouth disease.

The 2006 census took place on 23 April 2006. According to the 2006 form, "any person who fails or refuses to provide information or who knowingly provides false information may be subject to a fine of up to €25,000," under the Central Statistics Act 1993. On the CSO website, instructions for non-English speaking residents of Ireland were available. They were mock copies of the census forms, with all headings/questions etc. being translated into a particular language. These were not to be filled out, but were only a guide on how to fill out the English or Irish form. This census also asked two new questions relating to ownership of PCs and Internet connection.

Data from the Census of Ireland, 1901 and 1911 Census of Ireland were made publicly available in 1961, and are published online. Subsequent census records will be made publicly available 100 years after collection. In June 2010, the 1901 census of Ireland became available on the Internet.

Questions relating to the ability to speak the Irish Language are included in the census. The figures obtained have been criticised as inflated by cognitive biases, such as response bias or wishful thinking. The 2006 census included an additional question on frequency of speaking Irish.

The 2011 Irish Census was conducted on 10 April 2011. There have also been two campaigns asking people to consider how they answer the question on religion. As with the question relating to the Irish language, the accuracy of the figures for religious membership have been questioned.

Israel

The first census in the state of Israel was held in November 1948, six months after its creation, to establish the population registry. Subsequent censuses were conducted by the Israel Central Bureau of Statistics (ICBS) in 1961, 1972, 1983 and 1995. In these, 20% of households completed a detailed survey and the remainder a shorter questionnaire. There is no legal requirement to hold a census within a given interval; in practice, the ICBS requests and the government decides. The next Census to be held was postponed from 2006 to late 2008/early 2009. Only the detailed survey of 20% will be carried out, as a cost-saving measure.

Italy

The census in Italy is carried out by ISTAT every 10 years. The last five were in 1971, 1981, 1991, 2001 and 2011.

Japan

Japan collects census information every five years. The exercise is conducted by the Statistics Bureau of the Ministry of Internal Affairs and Communications. October 1, 2010 is Population Census Day.

The census-form solicits information on name, gender, relationship to head of household, year and month of birth, marital status, nationality, number of members of household, type and nature of dwelling, floor area of dwelling, number of hours worked during the week prior to October 1, employment status, name of employer and type of business, and kind of work.

Regardless of nationality, all residents in Japan are required to complete the census form. Census form is only written in Japanese, but translation is available upon request in 27 different languages. Online census is only available in Japanese.

All information collected by census is confidential and protected by Statistics Act. Information provided by census can never be used for any investigation purposes such as immigration control, police investigation, tax collections and so on. After the census, all forms are destroyed and recycled.

In Tokyo, people can choose to answer the census questions by filling out the paper form, or they can choose to answer census questions online. Unique ID and password are provided with the census form. The online census form is only available for residents of Tokyo. This is because a high concentration of people in Tokyo are living in apartment buildings or gated communities, which restricts the access of census workers.

Jordan

The first population census after the independence in 1946 was taken in 1952. It did only count the number of people in the households and could therefore be considered only to be a housing census. The first real complete census was taken in 1961. The following censuses have been taken in 1979, 1994 and 2004. The distribution of Palestinians and Jordanians within the population has been a politically sensitive issue since the Six-Day war in 1967.

Kenya

Census in Kenya was first held in 1948, when Kenya was still a Colony administrated by the British. Since 1969 census has been taken every ten years. The last census to date was in 2009. Kenya is the first African country to produce a completely processed census within one year after census

Kosovo

Kosovo, administrated by the UN since 1999, declared independence in 2008. Kosovo government is planning a general population census for 2011. The first census was conducted in the Kingdom of Serbs, Croats and Slovenes in 1921.

Latvia

The most recent census in Latvia was in 2011. Before that, it was about 7 censuses, most part of these previous censuses was undertaken during Soviet (USSR) control. The census in Latvia is carried out by Centrālā Statistikas Pārvalde (Central Statistical Bureau).

Lebanon

No census has been conducted in Lebanon since 1932. It indicated a population of 861,399 Lebanese. Various estimates of the population have been taken since; in 1956 it was estimated a population of 1,411,416, with 54% Christian and 44% Muslim. Conducting a census since then has been complicated by various conflicts in the 1970s and 1980s, as well as by the sensitivity of religious issues.

Malaysia

The census in Malaysia is carried out every 10 years, like many nations, since 1960 (with the exception of the fourth census, which was carried out in 1991). The next census will be carried out from July 6 to August 22, 2010, the most recent was in 2000.

Macedonia

The foundation of the Republic of Macedonia followed the breakup of the former Yugoslav Republic in 1991. The first population and housing census was taken in the summer 1994. The second census was taken in the autumn 2002. Both censuses were observed by international experts due to the sensitive issue regarding the ethnic distribution (Macedonian vs Albanian population).

Mauritius

Population and housing censuses for Mauritius was collected in 1972, 1983, and 2000; although respondents were asked to identify their race/ethnic origin in the 1972 census, this question was dropped from the following censuses because "the government felt that it was a divisive question". The Statistics Act of 2000 directed that all official censuses be conducted by the Central Statistics Office of Mauritius, as well as serve as the central depository for this information.

Mexico

Population censuses are taken every 10th year in Mexico. The latest have been in 1960, 1970, 1980, 1990, 2000, 2005 and 2010. After 1990 the Mexican census has been taken every 5 years.

Mozambique

The first census was taken in 1980. The second in 1997. The third was taken 1–14 August 2007.

Netherlands

The first census in the Netherlands was conducted in 1795, and the last in 1971. A law was produced on April 22, 1879, ordering a census to be conducted every ten years.

The census that was planned for 1981 was postponed and later cancelled. A call for privacy was responsible for the cancellation of any further census since 1991. Censuses are being conducted by the Centraal Bureau voor de Statistiek since 1899. The censuses today are mostly (population, fiscal) register based, combined with surveying.

New Zealand

The census in New Zealand is carried out by Statistics New Zealand (Tatauranga Aotearoa), on each year ending in a 6 or a 1 (every five years). The last was on 7 March 2006. For the 2006 Census of New Zealand, respondents could choose to complete their census questionnaire online. See New Zealand Census of Population and Dwellings. The Census scheduled for 8 March 2011 was cancelled due to the February 2011 Christchurch earthquake. It has been announced that the cancelled census will be held in 2013. It is not known whether the following census will be held in 2016, or whether the five-year time-frame will start anew.

Nepal

Population censuses are conducted every tenth year in Nepal. The first was held in 1911 and the most recent was held in 2011.

Nigeria

Population censuses have been taken in Nigeria during colonial time in 1866, 1871, 1896, 1901, 1911, 1921 and 1952. The censuses covered only the southern part of the country except for the 1952 census which was country wide, and the censuses before 1921 were based on administrative estimates rather than on an actual enumeration.

Censuses during the independence were taken 1963, 1973, 1991 and 2006. The results from 1973 and 2006 were highly disputed. The preliminary results for 2006 indicates a population of 140,000,000. 700,000 enumerators were engaged in this operation.

Norway

The two first male censuses was conducted during the 1660s and 1701. Later statistical censuses were held in 1769, 1815, 1835, 1845, and 1855. Norway's first nominative, complete census was taken in 1801, when Norway still was ruled by the Oldenburg dynasty of Denmark-Norway. The scope of the census followed the de jure principle, so military persons should be included as well as foreigners if they were residents. The 1801, 1865, 1900 and 1910 censuses are transcribed and made searchable on the internet. The census records are made publicly available when 100 years have passed. Since 1900, a census has been conducted every ten years. (However, the 1940 census was postponed to 1946, and the census after 1990 came in 2001.) Since 2001 the population census has been combined with the housing statistics. The 2001 questionnaire only asked about households and who was living in them, while no questionnaires will be mailed out for the 2011 census, since the administrative data on households is sufficient.

Oman

Censuses have been taken in the Sultanate of Oman in 1993 and 2003.

Pakistan

The first Pakistani census after the proclamation of independence was conducted in 1951. It was decreed that censuses have to be carried out once in 10 years. The second census was conducted in 1961. However the third one was conducted in 1972 because of Bangladesh Liberation War. The fourth census was held in 1981.The fifth census was delayed to March 1998. The sixth census of Pakistan was planned for October 2008. But due to some internal problems, the census was delayed till start of 2011 and its first phase was started in April allover the country.

Peru

The first census in Peru was carried out in 1836. The 11th and latest one was the 2007 Census and was carried out by Instituto Nacional de Estadística e Informática in August 2007.

Philippines

The census of the Philippines is enumerated every 5 years (beginning on 1960, except in 2005 where it was moved to 2007 due to budgetary constraints) and the results are used to allocate Congressional seats (congressional apportionment) and government program funding.

The census is performed by the Philippines' National Statistics Office. The first official census in the Philippines was carried out by the Spanish government pursuant to a royal decree calling for the counting of persons living as of the midnight of December 31, 1877. The first door-to-door census was conducted in 1903 to fulfill Public Act 467 which was approved by the U.S. Congress in July 1902. The last national census was held in 2007 and the next census is scheduled for 2010. For years between the censuses, the NSO issues estimates made using surveys and statistical models.

Poland

The census in Poland is carried out by GUS every circa 10 years. The last one occurred in 2002 between May 21 and June 8. During the national census in 2003 the following censuses were conducted at the same time: National Population and Housing Census and National Agricultural Census.

Portugal

The first census in Portugal was carried out in 1864. The census in Portugal is carried out by Instituto Nacional de Estatística (INE) every 10 years. A census was taken in 2001 and in March and April 2011.

Romania

The first census in Romania was carried out in 1859. It is now carried out every ten years by the Institutul Naţional de Statistică (INSSE). The last census was in 2011.

Russia and USSR

In Russia, the first census of the tax-payers was made in 1722-1723 by the order of Peter the Great (only men were counted), and was ordered to be repeated every twenty years. The only complete Russian Empire Census was carried out in 1897. All-Union Population Censuses were carried out in the USSR (which included RSFSR and the other republics) in 1920 (urban only), 1926, 1937, 1939, 1959, 1970, 1979, and 1989. The first post-Soviet Russian Census was carried out in 2002, followed by the 2010 Census. Currently, the census is the responsibility of the Federal State Statistics Service.

Saudi Arabia

Population censuses have been taken in Saudi Arabia in 1962/63 (incomplete), 1974 (complete but not reliable), 1992, 2004 and 2010. An agriculture census was taken in 1999.

Serbia

The census ordinarily takes place every 10 years. The last census was in 2002 (although having been planned for 2001), the previous one was in 1991 and the next is planned for 2011. The censuses before were organized in 1981, 1971, 1961, 1953 and 1948, during Communist Yugoslavia. During the Kingdom of Yugoslavia, censuses were conducted in 1931 and 1921; the census in 1941 was never conducted due to the outbreak of WWII.

The independent Princedom of Serbia, had conducted the first population census in 1834; the subsequent censuses were conducted in 1841, 1843, 1846, 1850, 1854, 1859, 1863 and 1866 and 1874. During the era Kingdom of Serbia, six censuses were conducted starting on 1884 and the last one being in 1910. And then the frequent wars had prevented organizing any census prior to the Yugoslav one in 1921.

For the portions of Serbia ruled by Austria-Hungary until 1918, there were a total of 5 Austro-Hungarian censuses - 1910, 1900, 1890, 1880 and 1869, immediately after the Dual Monarchy's constitution.

Slovakia

First modern census in the area of today's Slovakia was taken in 1869. Today, the census is conducted every 10 years by the Statistical Office of Slovak Republic. Last census was in May 2011.

Slovenia

The first census of modern Slovenia was carried in 1991, after independence had been declared. The Statistical Office of the Republic of Slovenia conducted the second census in 2002. Further censuses will be carried out in 2011 and then every 10 years.

South Africa

The first census of South Africa was taken in 1911. Several enumerations have occurred since then, with the most recent two being carried out by Statistics South Africa in 1996 and 2001. A census is currently being undertaken from 10 October to 31 October 2011, with results expected to be released in March 2013.

Spain

The census in Spain is carried out by INE every 10 years. Although there has been an old tradition and like for making census in Spain, the oldest ones dating back to the 12th century (by Alfonso VII of the Kingdom of Castile), the first modern census was carried out in 1768 by Conde de Aranda, under the reign of Carlos III. The last four were in 1971, 1981, 1991, and 2001.

Sri Lanka

The census in Sri Lanka is carried out by the Department of Census and Statistics every 10 years, with the next one being planned for 2011. The 2011 one being the first post-war census in three decades. The census will cover all Grama Niladhari (GN) divisions of the country.The first scientific census in Sri Lanka was conducted on 27 March 1871. The last four were in 1963, 1971, 1981 and 2001 with a census estimate in 1989. The 2001 census was only carried out in 18 Districts due to the Sri Lankan Civil War.

Sudan

Population censuses have been carried out in Sudan in 1955/56, 1973 (national), 1983 (national) and 1993 (only north). A census was conduced in April 2008. Some areas were difficult to measure (e.g. Darfur, Juba and Malakal)

Sweden

The first population census in Sweden was carried out in 1749. The last population and housing census was carried out in 1990. It is planned to conduct population and housing censuses based on registers in the future.

Switzerland

In Switzerland, the Federal Population Census (, , , ) has been carried out every 10 years starting in 1850. The census was initiated by Federal Councillor Stefano Franscini, who evaluated the data of the first census all by himself after Parliament failed to provide the necessary funds. The census is now being conducted by the Swiss Federal Statistical Office.

Data collected include population data (citizenship, place of residence, place of birth, position in household, number of children, religion, languages, education, profession, place of work, etc.), household data (number of individuals living in the household, etc.), accommodation data (surface area, amount of rent paid, etc.) and building data (geocoordinates, time of construction, number of floors, etc.). Participation is compulsory and reached 99.87% of the population in 2000.

Since 2010, the population census has been carried out and analysed annually in a new format by the Federal Statistical Office (FSO). In order to ease the burden on the population, the information is primarily drawn from population registers and supplemented by sample surveys. Only a small proportion of the population (about 5%) is surveyed in writing or by telephone. The first reference day for the new census was 31 December 2010.

Syria

The first population census in Syria was taken by the French Mandatory Regime in 1921-22. This is however not considered reliable. Censuses during independence have been taken 1947, 1960 (the first comprehensive demographic investigation), 1970, 1976 (a sample census), 1981, 1994 and 2004 and the next would be taken at 2017.

Taiwan

The first census in Taiwan was conducted in 1905, while Taiwan was under Japanese rule.

Turkey

The Turkish census is run by the Turkish Statistical Institute. The first census in Turkey was conducted in 1927. After 1935, it took place every 5 years until 1990. Now, the census takes place every 10 years. The last census was in 2000. It can be noted that the census enumeration takes place on one single day in Turkey (in other countries it takes 1–2 weeks). This required some 900,000 enumerators in 2000. The 15th census based on improved geographical information systems is planned for 2010.

A census was taken in the Ottoman Empire 1831-38 by Sultan Mahmud II (1808–1839) as a part of the reform movement Tanzimat. Christian and Jewish men were counted but the female population was excluded.

Uganda

The first censuses in Uganda were taken in 1911, 1921 and 1931. It was done in a rather primitive way. The enumeration unit was 'huts' and not individuals. More scientific censuses were taken 1948 and 1959 where the enumeration unit was persons. The census was however divided into two separate enumerations, one for Africans, and one for the non-African population. The censuses during independence 1969, 1980, 1991 were taken jointly for all races. The censuses 1980 and 1991 included housing information and in addition a larger questionnaire for a sample of the population. However, the questionnaires for the 1980 were lost and only provisional figures are available from this census.

The census in 2002 involved some 50,000 enumerators and supervisors. It covered several topics including: population and housing; agriculture; and Micro- and small Enterprises administered at individual/household level. The Preliminary Results were published two weeks after the enumeration. The Final Results were released in March 2005, while the analytical findings and the district level results were scheduled to be released in the second quarter of 2006.

Ukraine

The first post-Soviet Ukrainian Census was carried out by State Statistics Committee of Ukraine in 2001, 12 years after the last All-Union census in 1989.

===United Kingdom===

In the 7th century, Dál Riata was the first territory in what is now the UK to conduct a census. The Domesday Book of 1086 in England contained listings of households but its coverage was not complete and its intent was not the same as modern censuses.

Following the influence of Malthus and concerns stemming from his An Essay On The Principle Of Population the UK census as we know it today started in 1801. The census has been conducted every ten years since 1801 and most recently in 2011.

The first four censuses (1801–1831) were mainly headcounts and contained little personal information. The 1841 Census, conducted by the General Register Office, was the first to record the names of everyone in a household or institution. From 1851 onwards the census shows the stated age and relationship to the head of household for each individual. Because of World War II, there was no census in 1941. The actual census dates were 1841-06-06, 1851-03-30, 1861-04-07, 1871-04-02, 1881-04-03, 1891-04-05, 1901-03-31, 1911-03-27.

The census of England & Wales is undertaken for the government by the Office for National Statistics (ONS). The General Register Office for Scotland (GROS) conducts its own census, while the census in Northern Ireland is carried out by the Northern Ireland Statistics and Research Agency (NISRA). Public access to the census returns is restricted under the terms of the 100-year rule. The most recent returns made available to researchers are those of the 1911 Census.

The United Kingdom Census 2011 took place on 27 March 2011.

United States

The United States Constitution mandates that a census be taken every ten years in order to apportion the number of members of the United States House of Representatives among the several states. Census statistics are also used in order to apportion federal funding for many social and economic programs.

The first U.S. Census was conducted in 1790 by Federal marshals. Census takers went door to door and recorded the name of the head of the household and the number of people in each household. Slaves were enumerated, but only three out of five were counted for apportionment. American Indians, being neither taxed nor considered during apportionment, were not counted in the census. The first census counted 3.9 million people, less than half the population of New York City in 2000.

During the 19th century and through the 1940 census, enumeration was accomplished through political districts. Each ward was responsible for producing a census. The usual method in urban areas was to assign the task to precinct leaders, who in turn would hire and send out "census takers", equipped with pencils, a sheaf of forms, and assigned areas to canvass door-by-door. These census takers would return their forms to the precinct office, which forwarded them to the ward office, where the pencilled-in data was transcribed in ink to bound volumes. This transcription process resulted in numerous misspellings if the worker's handwriting was hard to read, as well as omissions of people who were not home on the day the canvasser was sent out. In rural areas, canvassers often had to cover miles of uninhabited rural territory to find small towns and isolated farms, missing many or simply refusing to travel the full distances required for one day's pay. Canvasser supervisors often were unaware of data omissions due to the intentional isolation of many people in the countryside.

From 1950 onward, census forms were mailed to every address on record with the United States Post Office, including the Armed Services Postal System, in an effort to enhance completeness of the data collected. Beginning in 1970, it was made illegal to fail to return a completed census form, which many were discovered to have done in the previous two decades' censuses. Canvassers came to be used only to verify a random sample of censuses received, and to attempt to complete records for people who still failed to return their census forms on time. Additionally in 1970, computer technology was introduced to consolidate the individual-completed census forms and canvassers' followup forms, in lieu of pen-and-ink transcriptions to official census ledgers.

The 2000 census counted over 281 million people. In 1891, the building containing the accumulated census records for 1890 caught fire, destroying all but a few pages of that decade's census: canvassers records were routinely destroyed once transferred to the official ledgers. In 1902, Congress established the Census Bureau as a federal agency.

In recent times, there have been two forms of questionnaire, long and short. The long form and its additional questions about matters such as daily commute times, housing unit factors, etc., has been replaced by the American Community Survey (ACS). Computer algorithms (based on complex sampling rules) determined which form was mailed to a given household, with one in six receiving the long form. This was supplemented by census workers going door to door to talk to those who failed to return the forms. In addition to a simple count of residents, the Census Bureau collects a variety of statistics, on topics ranging from ethnicity to the presence of indoor plumbing. While some critics claim that census questions are an invasion of privacy, the data collected by every question is either required to enforce some federal law (such as the Voting Rights Act) or to administer some federal program. The United States Congress gives approval to every question asked on the census.

Despite a massive effort, the Census Bureau has never been able to count every individual, leading to controversy about whether to use statistical methods to supplement the numbers for some purposes, as well as arguments over how to improve the actual head count. The Supreme Court ruled that only an actual head count can be used to apportion Congressional seats; however, cities and minority representatives have complained that urban residents and minorities are undercounted. In several cases, the Census Bureau has recounted an area with disputed figures, provided the local government paid for the time and effort. The state of Utah protested the figures of the 2000 decennial census because it stood to gain a seat in the House of Representatives, but North Carolina gained it instead. Had the Census Bureau been mandated to count the numbers of Utahns living overseas, including many Mormon missionaries, Utah might have gained the seat.

To minimize the burden on individuals and to provide improved data, the Bureau has prepared several alternate methods for gathering economic, demographic, and social information, including the American Community Survey and record linking of depersonalized administrative records with other administrative records and Census Bureau surveys.

By law (92 Stat. 915, Public Law 95-416, enacted on October 5, 1978), individual census records are sealed for 72 years. This figure has remained unchanged since before the 1978 law, reflecting an era when life expectancy was under 60 years, and thus attempts to protect individuals' privacy by prohibiting the release of personal information during individuals' lifetimes. The individual census data most recently released to the public was the 1930 census, released in 2002. Aggregate census data are released when available.

In addition to the decennial federal census, local censuses have also been conducted, for example, in Massachusetts, which conducted a statewide census every five years until 1985. Additionally, each community in Massachusetts takes a municipal census each year. Some states conducted limited censuses for various purposes, and these are typically located in state archives.

See also

Census Day

Demographics

Early European population statistics and censuses

intercensal estimate

Liber Censuum

Social research

Notes

References

Alterman, Hyman. Counting People: The Census in History. Harcourt, Brace & Company 1969.

Bielenstein, Hans. "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, 223-90 (Cambridge: Cambridge University Press, 1978).

Effects of UK 'Jedi' hoax on 2001 UK census from ONS.

Kruger, Stephen, "The Decennial Census", 19 Western State Law Review 1 (1981).

U.S. Census Press Release on 1930 Census.

U.S. Census Press Release on Soundex and WPA.

External links

Census of Ireland 1911.

Online Historical Population Reports Project (OHPR).

PR as a function of census management: comparative analysis of fifteen census experiences

Category:Censuses Category:Genealogy Category:Population Category:Demography Category:Survey methodology Category:Sampling (statistics)

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