Undocumented Residents in the United States in 1990: Issues of Uncertainty in Quantification
Censuses and national surveys are monitoring net immigration to the United States as the twentieth century closes with high immigration reminiscent of the early decades. These demographic studies inferred the legal-undocumented composition for census and national survey estimates for the foreign-born population. For both net immigration and that portion attributable as net legal immigration, an increasing trend is evident since 1970. Uncertainties are abundant about the measurement of net undocumented migration and change over the past two decades. This analysis presents possible upper and lower boundaries on components for estimating legal migration in 1980–1989 and on the foreign-born population in 1990. Positing ranges for net undocumented immigration; between 2 million and 4 million undocumented residents may have been counted in the 1990 census. The total number of undocumented residents may have been as high as 6 million. To more narrowly specify these ranges, greater exercise of judgment would be necessary but not sufficient.