Comparability — Argentina [top]

In the 1991 sample, roughly half the cases lack data for this and several other variables. Users should apply the alternative weight variable AR1991A_0434 when using one of these variables.

The 1991-2001 classifications are fundamentally different from the earlier samples and from other countries. They reflect a more industrial and skills-based organization.

The universe changes over time, ranging from age 10 or older to age 14 or older in 1980.

Comparability — Armenia [top]

The sample uses the ISCO 1988 classification.

Comparability — Austria [top]

The source data for Austria assigned occupations to non-workers based on who "supported" them. OCC reports data only for economically active persons.

The 2001 sample has an alternative, more detailed occupation classification among the unharmonized source variables.

Comparability — Belarus [top]

The Belarus 1999 and 2009 samples follow the ISCO 1988 classification system. The reference period is the week prior to the census for the both samples.

Comparability — Benin [top]

The 2013 sample uses the ISCO 1988 classification, while the earlier samples use ISCO 1968. The universe varies across samples.

Comparability — Bolivia [top]

The universe for occupation is different among Bolivian samples. In 1976 and 1992, the person's occupation during the last week was recorded for both employed and unemployed persons age 7 or older. If a person was unemployed, the most recent or usual occupational activity was recorded. In 2001 and 2012, occupation was only recorded for persons age 7 and older who worked during the week prior to the census, or had a job but did not work due to temporary absence (vacation, illness, personal business, etc.).

The 2012 sample follows the ISCO 2008 classification system.

Comparability — Botswana [top]

The 1981 sample follows the ISCO 1968 classification system. The 1991-2011 samples use a classification system that is the national version of ISCO 1988.

The reference period for the 1981-1991 samples was the past month, but it changed for the 2001-2011 samples to the week prior to the census.

Comparability — Brazil [top]

The question aims to record the person's usual occupation: the one the respondent practiced for the most time in the prior year (for the 1960-1991 samples), or the prior week (for the 2000 and 2010 samples). However, for all samples, no person is recorded with an occupation if they were out of the labor force at the time of the census.

The 2010 sample follows the ISCO 2008 classification system.

Comparability — Burkina Faso [top]

The universe statement differs across samples. The 1985 and 1996 samples use the same occupation coding scheme. Occupation data were collected in 2006, but the codes are undocumented.

Comparability — Cambodia [top]

All samples include employed and unemployed persons and use very similar classifications based on the ISCO system. They report main activity performed last year.

Comparability — Cameroon [top]

The universe statement differs across samples with respect to employment status, age, and household type.

The 1976 sample uses a unique classification system. The 2005 sample classified occupation in accordance with the 1988 ISCO system.

Comparability — Canada [top]

The Canada sample data do not have much occupational detail, except for 2011, and are based on national occupational classifications not fully equivalent to ISCO. The classifications for 1971 to 1991 were quite consistent.

Comparability — Chile [top]

The age universe changes over time. The codes differ between years except for the 1970-1982 samples. The 2002 sample identifies far fewer occupations than the other years.

Comparability — China [top]

Persons temporarily absent from their job reported their regular occupation. Those with multiple occupations reported the one in which they spent the most time.

The China 2000 sample has a more aggregated occupational grouping available with respect to 1982 and 1990.

Comparability — Colombia [top]

The question recorded the current main occupation for employed persons, and the last occupation held for unemployed persons.

Comparability — Costa Rica [top]

The variable records the person's main occupation at the time of census or, prior to 2000, when they were last employed. The occupation codes for 1973 and 1984 are similar to one another. OCC is not available for the 1963 sample.

Comparability — Cuba [top]

The universe is consistent across the 2002 and 2012 samples, and the reference period for both samples is the week prior to the census. The 2002 sample uses a national classification based on the ISCO 1988 system, while the 2012 sample uses a national classification based on the ISCO 2008 system.

Comparability — Côte d'Ivoire [top]

The occupation labels in the 1998 sample were originally in French and based on the ISCO88 classification.

Comparability — Dominican Republic [top]

The 1960, 1970 and 1981 samples each use a unique classification system. The 2002 and 2010 samples use the ISCO 1988 classification system.

The universe changes over time. In 1960, the question was asked of persons age 10 and older who were employed between January 1st and August 7th, 1960. In 1970, the question was asked of persons age 10 and older who were employed or unemployed the week prior to the census. In 1981-2010, the question was asked of persons age 10 and older who had ever worked. Respondents who had worked before but were not working during the week prior to the census reported their last occupation.

Comparability — Ecuador [top]

The age universe changes over time. The occupation codes differ between samples. The 2010 sample follows the ISCO 2008 classification scheme.

Comparability — Egypt [top]

The 1986 sample uses the ISCO 1968 classification, while the1996 and 2006 samples use ISCO 1988. The age universe of respondents changes from 15 and older in 1986-1996 to 6 and older in 2006.

Comparability — El Salvador [top]

Both samples use the ISCO classification and differ only in coverage of unemployed persons.

Comparability — Ethiopia [top]

The 1984 sample uses the ISCO 1968 classification, requiring some recoding. The 1994 sample uses ISCO 1988. The 2007 sample does not contain occupation information.

Comparability — Fiji [top]

The sample universes differ slightly with respect to age and whether all workers are included in the universe or whether it is restricted to those who worked for money. The 1976 and 1986 samples use the 1968 ISCO system, while the later samples use the 1988 and 2008 ISCO classifications.

Comparability — Finland [top]

The one-digit coding structure for the 2010 sample is consistent with the ISCO 2008 classification system.

Comparability — France [top]

The codes for OCC are comparable across the 1962-1990 samples. The 1999 differs from the earlier years, with more detail. The 2006 and 2011 classifications are also detailed and use a common classification.

In all samples, unemployed persons report their occupations. The universe differs slightly across samples with respect to age.

Comparability — Ghana [top]

The 1984 and 2000 samples use the ISCO 1968 classification system. The 2010 sample uses the ISCO 2008 classification system. The universe differs slightly across samples in terms of minimum ages.

Comparability — Greece [top]

The 1971-1991 samples use the same classification. The 2001 census used a version of the ISCO 1988 classification, while the 2011 census occupational data are based on ISCO 2008.

Comparability — Guatemala [top]

The 1964-1981 samples use their own classification, which is very similar to the COTA system. The 1994 and 2002 samples both used the ISCO 1988 classification system.

Comparability — Guinea [top]

The 1996 and 2014 samples record occupation for residents age 6+ who were employed or experienced unemployed, while the 1983 sample records occupation for persons age 10+ who were employed or unemployed.

The classification system differs across samples. The 2014 sample uses a classification scheme based on the ISCO 1988 system.

Comparability — Haiti [top]

While the samples have the same universe, the reference period for employment is different across years. The 1982 sample uses the 1968 ISCO classification scheme; the 2003 sample uses the 1988 ISCO codes.

Comparability — Honduras [top]

The 1960 sample uses the COTA 1960 classification. The 1974 and 1988 samples use a unique classification. The 2001 sample uses the ISCO 1988 system. The 2013 sample uses the ISCO 2008 system. The universe in 2001 and 2013 differs from the previous samples.

Comparability — Hungary [top]

The occupation data in the Hungary samples are comparable, as they follow some ISCO coding structure. In 1970-1990, occupations are coded using a national classification equivalent to ISCO 1988. The 2001 sample applies ISCO 1988 and the 2011 sample uses ISCO 2008.

Comparability — Indonesia [top]

The samples use the same basic underlying classification (ISCO-68) with similar universes.

Comparability — Iran [top]

The 2006 and 2011 samples report the current occupation of employed persons aged 10 or more.

Comparability — Ireland [top]

The universe statement changes significantly over time. It includes employed, and sometimes unemployed, persons in the samples between 1971 and 1991. In the 1996-2016 samples, it consists of persons who were working or experienced unemployed, with an additional exclusion of absent persons in the 2002-2016 samples.

The samples use a number of different occupation classifications, none of which are based on ISCO. The 1986 and 1991 samples use the same classification, as do the 1996-2006 samples. The 2011 and 2016 samples also use the same classification system, although the 2016 sample only records one-digit codes while the 2011 sample records three-digit codes.

Comparability — Israel [top]

The samples use a national classification system of broad occupational categories that is relatively consistent across time. The universe for all samples consists of persons who worked in the previous year, although the age universe differs between the 1972 and 1983-2008 samples.

Comparability — Italy [top]

The censuses both have simple 1-digit classifications with different codes and labels.

Comparability — Jamaica [top]

The 1982 sample records the occupation of anyone who ever worked. The latter samples limit the universe statement to persons currently in the labor force, although all persons who ever worked were asked the question.

All samples use the ISCO classification system.

Comparability — Kenya [top]

In 1989 and 2019, the question applied to employed persons, whether at work or not; both samples include specifically persons on leave or sick leave, and the 1989 sample also mentions persons working on family holdings.

Despite the universe statement, occupations also are reported for some persons seeking work, students, retired persons, disabled persons, homemakers, and others.

NOTE: In 1989, only a small fraction of persons actually reported an occupation. The meaning of these data is questionable.

Comparability — Lesotho [top]

The 1996 sample uses the ISCO 1968 while the 2006 sample uses the ISCO 1988 classification system. In the 1996 sample, professionals and technicians cannot be separated. The universe is slightly different between the two samples.

Comparability — Liberia [top]

The 1974 sample uses the ISCO 1968 classification system. The 2008 sample uses the ISCO 1988 classification system and did not require recoding. The universe differs slightly across samples in terms of minimum ages.

Comparability — Malawi [top]

The 1987-2008 samples use nearly identical classifications, while the 2018 data uses a different coding structure and provides less detail.

The samples have age universe differences: 10 and older in 1987, 1998, and 2018, while 6 and older are considered in 2008. The 2018 sample considers only persons who worked in the prior week, while the 1987, 1998, and 2008 samples also comprise unemployed respondents.

Comparability — Mali [top]

The samples use entirely different occupational classifications, but the universe is consistent over time.

Comparability — Mauritius [top]

The universe is identical across the three samples. The 1990 and 2000 samples use the ISCO 1988 classification system, while the 2011 sample uses a coding structure that is consistent with the ISCO 2008 classification system.

Comparability — Mexico [top]

The Mexico samples use national classifications to code occupations. The 1990-2000 samples used the same classification, while the coding structure is also common across 2010-2015 and is based on ISCO 2008. The 1960 and 1970 samples used their own classification systems.

In 1970, the question applied to the occupation the person held during the previous year, regardless of employment status at the time of the census. In 1990, 2000, 2010, and 2015, the question was addressed only to employed persons.

Comparability — Mongolia [top]

In 2000, the occupational classification was based on ISCO. The 2010 and 2020 samples use the ISCO-2008 classification and the data are comparable across.

Comparability — Morocco [top]

The 1982 sample uses a different underlying classification system than the one employed in the 1994-2014 samples. The universe for the 2004-2014 samples consists of persons who were employed or experienced unemployed, while the universe for the 1982-1994 samples includes only persons who were working.

Comparability — Mozambique [top]

The 1997 and 2007 samples use the ISCO 1988 classification. The 2017 sample uses the ISCO 2008 classification system. There are minor differences in the universes across the three samples.

Comparability — Myanmar [top]

The 2014 sample uses the ISCO 1988 classification system.

Comparability — Nepal [top]

The Nepal samples use the ISCO 1988 classification system.

Comparability — Nicaragua [top]

The 1971 sample uses a different underlying classification. The 1995 and 2005 samples use ISCO.

Comparability — Palestine [top]

All three samples use the 1-digit ISCO classification system and are fully comparable, apart from minor universe differences.

Comparability — Panama [top]

The universes are comparable with respect to age, but differ slightly by employment status. The 2000 and 2010 samples follow the 1988 ISCO classifications for occupation. The earlier samples each use a unique classification system that varies somewhat over time.

Comparability — Papua New Guinea [top]

In 1980 and 1990, only urban workers are in the universe of respondents. All samples are compatible with the ISCO 1988 classification system.

Comparability — Paraguay [top]

The 2002 sample uses the ISCO 1988 classification, with only one digit of detail. Earlier samples use differing classifications.

Comparability — Peru [top]

The universe for the 1993 and 2007 samples include persons who are age 6+, the universe for the 2017 sample however, includes persons who are age 5+. The universe for the 1993 and the 2017 samples includes persons who worked or experienced persons who are seeking work, while the universe for the 2007 sample includes people who worked last week.

Comparability — Philippines [top]

The census samples use very similar classifications. The main difference is an extra digit in the codes of the 1990 sample. The classifications are comparable for major occupational groupings. Differences in the universe are due to the inclusion of non-occupational categories in the first major grouping of the 1990 sample.

Comparability — Poland [top]

The 1978 and 1988 used different occupational classification systems that are not compatible with ISCO. The 2002 sample has only large occupational groups available, but the coding structure follows ISCO.

The 1978 and 1988 source data assigned occupations also to non-workers based on who "supported" them, but OCC includes only data for economically active persons.

Comparability — Portugal [top]

The 1991 and 2001 classifications are nearly identical. The 2001 sample, instead, combines some categories that are separate in the 1991 one.

Comparability — Puerto Rico [top]

The universe varies somewhat between 1970 and the later samples. Several classifications are used by the different samples, but alternative and highly consistent classifications are also available among the source variables.

Comparability — Romania [top]

The coding structure is comparable for the 1992, 2002, and 2011 samples. The 1992 and 2002 samples used the ISCO 1988, whereas the 2011 census used ISCO 2008. The 1977 sample uses a different occupational structure that is not compatible with ISCO.

In the 1992 and 2011 samples, the universe statement includes persons who were either employed or seeking work. In the 1977 and 2002 samples, instead, the universe statement includes only persons who were currently employed.

The 1977 source data assigned occupation to non-workers based on who "supported" them. OCC reports data only for economically active persons.

Comparability — Rwanda [top]

The 2002 sample uses the ISCO 1988 classification while the 2012 uses the ISCO 2008 classification.

Comparability — Senegal [top]

The 2013 sample uses the ISCO 2008 classification system. The coding structures for the 1988 and 2002 samples are relatively consistent with the ISCO classification system, with some minor discrepancies. The universe differs between the 1988-2002 samples and the 2013 sample.

Comparability — Sierra Leone [top]

The data report the occupation of respondents who worked in the last 30 days for the 2004 sample and the past 12 months for the 2015 sample. Both samples use a 1-digit ISCO 1988 classification.

Comparability — Slovakia [top]

The samples use different occupation classifications over time. The data uses a national classification in 1991, ISCO 1988 in 2001, and ISCO 2008 in 2011. The occupation classification in the 1991 sample is more detailed than the classification in 2001 and 2011.

Comparability — South Africa [top]

All samples asked the question to currently employed persons. However, the age universe differs across samples. The samples all use the same occupational coding scheme.

Comparability — South Sudan [top]

This sample uses the 2-digit version of the 1988 ISCO classification system.

Comparability — Spain [top]

Retirees are included in the 1991 universe and excluded from the 1981, 2001, and 2011 samples. Therefore, there are significantly more persons with occupation responses in 1991 than in the other years. The classification scheme changes across samples.

Comparability — Sudan [top]

The sample uses the ISCO classification.

Comparability — Suriname [top]

The 2004 and 2012 samples both use the one-digit ISCO 1988 classification system and have fully comparable categories. The age universe differs across samples, as the 2004 universe consists of employed persons age 12+, while the 2012 universe consists of employed persons age 15-64.

Comparability — Switzerland [top]

The codes are consistent across samples and use the ISCO classification to record present occupation. For confidentiality reasons, occupations with very small frequencies are suppressed in some years and not in others. All samples also have alternative occupation classifications in the unharmonized source variables.

Comparability — Tanzania [top]

The occupation coding structure is identical between 2002 and 2012, while these two samples are comparable to 1988. The data for all the Tanzania samples are based in the ISCO system, although the 1988 sample has no categories for technicians and operatives.

Comparability — Thailand [top]

The universe statement for age differs between the 1970-1980 samples and the 1990-2000 ones.

The classifications differ between samples, but all have the last year as the reference period.

Comparability — Togo [top]

The 1960 and 1970 samples use their own classifications but they are comparable. The 2010 sample used a modified ISCO classification.

Comparability — Trinidad and Tobago [top]

The coding structure for the Trinidad and Tobago samples is largely comparable: the 1980 sample uses a classification based on ISCO 1968, while the 1990 and 2000 samples are based on ISCO 1988.

Comparability — Turkey [top]

All samples use the same classification.

Comparability — Uganda [top]

The 1991 and 2002 samples use nearly identical classifications and are fully comparable for major occupational groupings. However, the 2014 sample uses a different two-digit classification system. The universe differs across all three samples.

Comparability — United Kingdom [top]

All samples have alternative occupation and socioeconomic variables. OCC uses the census occupation classification from the 1991 and 2000 Standard Occupational Classification for the 2001 sample. See the unharmonized variables for other versions.

Comparability — United States [top]

All samples are conceptually comparable. The main difference is in the universe statement with respect to age, armed forces, and experienced workers not in the labor force. The 1980 and 1990 samples use the same classification system, which differed considerably from the one used in the 1960 and 1970 samples. The 2000 sample uses yet another, substantially different, classification. The first three digits of the 2010 codes are comparable to those used in 2000; however, the 2010 sample includes a fourth digit, which adds an additional level of detail.

Comparability — Uruguay [top]

The 1963 and 1975 samples each use a unique classification scheme. The 1996 and 2006 samples use ISCO. The 1985 sample uses COTA 1970.

The timing of the occupation changes across samples. In 1963, persons reported their occupation on the day of the census; in 1975, 1985, and 2006, persons reported their occupation during the past week, whereas in 1996 people provided information about their occupation during the last month.

The universe differs across samples: the universe in 1963 was composed of persons aged 8 years and older in the labor force, for the 1975-1996 samples the universe includes persons aged 12 years or older who were employed or experienced unemployed, while in 2006 the occupation was reported by occupied persons aged 14 or older.

Comparability — Venezuela [top]

The universe statement differs across samples. The 1990 sample includes persons who worked in the previous year. The 1981 and 1990 samples, instead, use the same occupational coding scheme. OCC is not available for the 1971 sample because the documentation did not match the values in the data.

Comparability — Vietnam [top]

The 1999 sample classified occupation in accordance with the 1988 ISCO system. The 2009 sample, instead, uses the 2008 ISCO system. The 1989 sample uses a radically different scheme that is non-hierarchical and highly industrial in character. In 1999, the question applied to persons who worked at least six of the previous twelve months. The 1989 and 2009 samples record the occupational status at the time of the census.

Comparability — Zambia [top]

The 1990 and 2000 samples use the ISCO 1968 classification system; the 2010 sample uses the ISCO 1988 classification system. The universe differs slightly across samples.

Comparability — Zimbabwe [top]

The 2012 sample uses the ISCO 1988 system.