Variables:
The variables used for each census year are described below.
1850: Those with a Spanish place of birth or a Spanish surname.
1860: Free, foreign-born inhabitants from Argentina, Bolivia, Chile, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Puerto Rico, Spain, Uruguay, or Venezuela.
1870: Free, foreign-born inhabitants from 'Spanish' countries (see the 1860 list).
1880: Foreign stock based on IPUMS Spanish surname or place of birth for self, mother, or father. If self, mother, or father were born in a 'Spanish' country (see the 1860 list) or if the person had Spanish surname, then that person is designated as Foreign Stock Hispanic.
1890: Same rule as 1880.
1900: Foreign stock based on IPUMS mother tongue of self, mother, or father (Spanish), language spoken (Spanish), or place of birth for self, mother, or father (a Spanish country). If self, mother, or father were born in 'Spanish' country (see 1860 list), or if any of the other conditions are true, then the person is designated as Foreign Stock Hispanic.
1910: Same rule as 1900.
1920: Foreign stock based on IPUMS mother tongue of self, mother, or father (Spanish), place of birth for self, mother, or father (a Spanish country - see 1860 list), or Spanish surname. If self, mother, or father were born in 'Spanish' country, or if any of the other conditions are true, then the person is designated as Foreign Stock Hispanic.
1930: Foreign stock based on IPUMS place of birth for self, mother, or father (a Spanish country - see 1860 list), or Spanish surname. If self, mother, or father were born in a 'Spanish' country, or any of the other conditions are true, then the person is designated as Foreign Stock Hispanic.
1940: Census Bureau estimate of Hispanics (any race) based on 5 percent sample. See "Total Population, White, Black, and Other, 1850-1990:
Historical Census Statistics on Population Totals By Race, 1790 to 1990, and By Hispanic Origin, 1970 to 1990, For The United States,
Regions, Divisions, and States." Campbell Gibson and Kay Jung.
http://www.census.gov/population/www/documentation/twps0056.html (June 21, 2006).
1950: Same rule as 1930.
1960: Persons having a Hispanic surname or whose mother tongue is Spanish or whose own, mother's, or father's place of birth was a Spanish-speaking country (see 1860 list).
1970: Census Bureau estimate of Hispanics (any race) based on 15 percent sample. See citation for 1940.
1980: Persons having a Hispanic surname or who speak Spanish or whose own, mother's, or father's place of birth was a Spanish-speaking country (see 1860 list) or who claimed Hispanic origin.
1990: Persons who speak Spanish or whose own birth place was a Spanish-speaking country (see 1860 list) or who claimed Hispanic origin.
2000: Persons who speaking Spanish or whose own birth place was a Spanish-speaking country (see 1860 list) or who claimed Hispanic origin.