Colombia: 1964, 1973, 1985, 1993
France: 1962, 1968, 1975, 1982, 1990
Kenya: 1989, 1999
Mexico: 1970, 1990, 2000
United States: 1960, 1970, 1980, 1990
Vietnam: 1989, 1999

Colombia 1964: Persons age 12+.
Colombia 1973-1993: Persons age 10+.
France 1962-1968, 1982-1990: Persons age 15+.
France 1975: Persons age 17+.
Kenya 1989: Persons age 10+.
Kenya 1999: Persons age 5+.
Mexico 1970-2000: Persons age 12+.
United States 1960-1970: Persons age 14+.
United States 1980-1990: Persons age 16+.
Vietnam 1989-1999: Persons age 13+.

EMPSTAT indicates whether or not the respondent was part of the labor force -- working or seeking work -- over a specified period of time. Depending on the sample, EMPSTAT can also convey further information. The first digit of EMPSTAT is fully comparable, and classifies the population into three groups: employed, unemployed, and inactive. The combination of employed and unemployed yields the total labor force. The second and third digits of EMPSTAT preserve additional information available for some countries and census years but not for others. Employment status is sometimes referred to in other sources as "activity status."

The age of persons to whom the question applies varies across the samples (see Universe).

The reference period for the employment status question varies. For most samples, employment status was reported with respect to the day of the census or within a specified week prior to the census. For Vietnam, however, the reference period was the previous year - amounting to "usual employment status" over this period. Short reference periods can have an impact on seasonal labor measures, depending on when the census was taken. The variations among samples with respect to reference period are summarized below:

Reference period:

1) Current (at time of census):

Colombia 1964

France 1962-1990

2) Reference week (typically "last week"):

Colombia 1973-1993

Kenya 1989-1999

Mexico 1970-2000

United States 1960-1990

3) Last year:

Vietnam 1989-1999

The unemployed population (and therefore the total labor force) is difficult to define consistently across countries. We have attempted to apply U.N. and ILO standards in defining the unemployed as persons who are out of work and actively seeking a job. Some countries have relatively small paid-labor sectors and irregular labor markets, making unemployment comparisons difficult. Kenya identifies persons not working simply because no work was available, explicitly denoting them as discouraged workers in 1999. Users should also be particularly careful when using the Vietnam samples, which determine employment status relative to the reference year. These Kenya and Vietnam responses are given unique detailed codes so that researchers can choose to interpret them as they wish. In general, where EMPSTAT is concerned, users should pay special attention to the enumerator instructions and forms.

Among the unemployed, some samples distinguish between persons with past work experience (experienced unemployed) and persons seeking work for the first time (new workers).

The number of categories distinguished among the inactive population varies widely among samples.

The United States samples separately identify active military personnel, and the French samples distinguish persons undergoing military training among other active workers.

The reference period for the employment status question applies to status at the time of the census in 1964, whereas in later years it applies to a reference week.

In 1964, experienced workers and new workers are not distinguished.

The age universe is 12+ in 1964 and 10+ in other years.

In 1975, employment status was determined for persons age 17 and older, whereas all other French samples provide this information for persons age 15 and older.

In all years the reference period was employment status at the time of the census.

The question itself has not undergone changes, but the extent of detail in the responses varies.

The 1962 Census distinguishes between experienced workers and those without previous work experience. Among the experienced unemployed in 1962, the census reports the number of months worked prior to becoming unemployed.

The 1962 sample does not identify retirees, but the later French samples do.

The 1968 Census has a separate category for those persons who work and study at the same time.

The age of persons to whom the question applies varies significantly across Kenyan censuses. For the 1989 Census the question applied to all persons age 10 and older and for the 1999 Census to all persons age 5 and older.

Kenya distinguishes persons working on family holdings from other active workers, and the 1999 sample distinguishes between agricultural and non-agricultural holdings.

Persons who report having "no work" are coded as inactive. The census instructions for 1989 simply imply that no work means the person did not have paid employment (aside from persons on family holdings). In 1999, the instructions state that the person was not looking for work "because he/she is discouraged, but would usually take up a job when offered one." These persons are given a distinct code for "no work available" so that researchers can identify them.

The universe and reference period are fully comparable across the Mexico samples.

The 2000 Census has categories for people who were "at work" but reported different additional situations such as seeking work, student, and houseworker, among others. Some of these combinations appear to contradict the "at work" classification, but all have been retained in order to allow researchers to make their own interpretations.

The 1970 Census did not provide detail on the inactive population except for "houseworkers," while the later samples have numerous subcategories.

In 1960 and 1970, the universe consisted of persons age 14 and older; in 1980 and 1990, of persons age 16 and older.

In all years the reference period was the "previous week"-- which would not have been the same for all respondents, since the census was taken over a period of time.

More detail about the content of the categories is available.

The reference period for employment status is the entire previous year ("usual activity"). The long reference period complicates the interpretation of the work status responses - particularly for unemployment.

The available employment status information differs greatly between the 1989 and 1999 samples, and the year-long reference period complicates the interpretation. In the 1989 Census there are three categories for the employed population: "persons that had been working more than 6 months in the last year," "persons that had been working permanently less than 6 months," and "persons that had been working temporally less than 6 months". However, for the 1999 Census, only those persons who had been working more than 6 months were considered employed. To make the categorization compatible, we have coded all persons working for less than 6 months in the 1989 sample as unemployed.

In 1989, the "unemployed, not specified" category contains persons available for work but who had not worked at all in the month previous to the census and had worked less than 6 months during the reference year. In 1999, the unemployed are those with no job but who said they had "demand for work" (i.e., were seeking work).