Estimating Illegal Migrants Counted in the Census, 1990 and 2000

Joe M. Costanzo, U.S. Census Bureau
Cynthia J. Davis, U.S. Census Bureau
Caribert Irazi, U.S. Census Bureau
Daniel Goodkind, U.S. Census Bureau
Roberto Ramirez, U.S. Census Bureau

As part of the Census Bureau's evaluation of Census 2000 and the determination as to whether the Census 2000 counts should be adjusted, the Population Division has reviewed its demographic analysis and population estimates methodology, and the underlying components of population change, including components of international migration. This report provides an evaluation of the illegal migration component of international migration as it relates to the U.S. resident population on April 1, 1990 and April 1, 2000. Estimates are calculated by age, sex, race, Hispanic Origin, place of birth, and components of international migration. Assumptions about undercoverage of the illegal population are derived as well. The methods behind these estimates and the estimates themselves are compared with contemporary findings.