Colombia: 1964, 1973, 1985, 1993
Kenya: 1989, 1999
Mexico: 1960, 1970, 1990, 2000
United States: 1960, 1970, 1980
Vietnam: 1989, 1999

Colombia 1964-1993: Persons age 5+.
Kenya 1989: Persons age 6+.
Kenya 1999: Persons age 5+.
Mexico 1960-1970: Persons age 6+.
Mexico 1990: Persons age 5+.
Mexico 2000: Persons age 6+.
United States 1960: Persons age 5+.
United States 1970: Persons age 3+.
United States 1980: All persons.
Vietnam 1989-1999: Persons age 5+.

YRSCHOOL indicates the highest grade/level of schooling the person had completed, in years. Only formal schooling is counted. YRSCHOOL accounts for the number of years of study, regardless of the track or kind of study. Information on degree and/or technical track is available in the EDATTAIN variable.

YRSCHOOL is top-coded differently across samples. All samples reported exact years of schooling through secondary school, but some had a maximum number or reported only a terminal degree such as "university" or "some university." All samples are top-coded at 18+ years. See the "codes" link above.

Some samples reported either the person's highest grade completed or the current grade if they were still attending school. Whenever a person was reported as attending a particular grade, we have assumed that the highest grade they had completed was one less than the grade they were currently attending. Persons currently attending school could conceivably have attained a higher level of education than indicated by their present level of study.

The "not specified" category contains responses that did not translate into a specific number of years of schooling. The second digit for these cases offers more detail.

Persons with a response of "special education" or "fundamental education" in the 1964 sample are coded as having completed zero years of schooling.

Colombia has eleven years of school before university entrance. The first year of university is therefore coded as twelve years of schooling.

The 1993 census only reports that a person reached the university level, not the specific number of years of tertiary/post-tertiary education completed. Persons with any university education are coded as having 12+ years of schooling, implying that they had completed at least one year of tertiary education.

Kenya added an extra year of primary school in 1985. All persons in secondary or higher levels who studied under the new system had an additional year of education. We use age to adjust years of schooling to account for this change. Because of differing ages of entering school and local variations, our calculation should be considered approximate.

The Kenyan censuses do not give detail for years of university study. The data are therefore top-coded at 13+ years.

YRSCHOOL is top-coded at 18+ years, although a few respondents claimed more years of university study.

In 1980, persons who had passed a high school equivalency examination (GED) were to indicate that they had completed twelve years of school.

The 1990 census asked for "educational attainment" (degree or milestone) rather than specific years of schooling. YRSCHOOL is therefore not available for the 1990 U.S. sample, but see EDATTAIN.

The Vietnam census only reports specific years of schooling for general school (grades 1 through 12). We have assigned persons with college or post-graduate degrees a minimum number of years of schooling appropriate to that level of study.