Pew Hispanic Center

Undocumented Immigration Now Trails Legal Inflow, Reversing Decade-Long Trend

by Jeffrey S. Passel, Senior Demographer, Pew Hispanic Center and D'Vera Cohn, Senior Writer, Pew Research Center
October 2, 2008

There were 11.9 million unauthorized immigrants living in the United States in March 2008, according to new Pew Hispanic Center estimates. The size of the unauthorized population appears to have declined since 2007, but this finding is inconclusive because of the margin of error in these estimates. However, it is clear from the estimates that the unauthorized immigrant population grew more slowly in the period from 2005 to 2008 than it did earlier in the decade.

It also is clear that from 2005 to 2008, the inflow of immigrants who are undocumented fell below that of immigrants who are legal permanent residents. That reverses a trend that began a decade ago. The turnaround appears to have occurred in 2007.

The Pew Hispanic Center also estimates that inflows of unauthorized immigrants averaged 800,000 a year from 2000 to 2004, but fell to 500,000 a year from 2005 to 2008 with a decreasing year-to-year trend. By contrast, the inflow of legal permanent residents has been relatively steady this decade. Although the growth of the unauthorized population has slackened, its size has increased by more than 40% since 2000, when it was 8.4 million. In 2005, the Pew Hispanic Center estimated there were 11.1 million undocumented immigrants in the United States. The most recent estimate, 11.9 million, indicates that unauthorized immigrants make up 4% of the U.S. population.

These estimates are based mainly on data from the 2000 Census and the March Current Population Surveys for the years since then. Because the Census Bureau does not ask people their immigration status, the estimates are derived using a widely accepted methodology that essentially subtracts the estimated legal-immigrant population from the total foreign-born population. The residual is treated as a source of data on the unauthorized immigrant population. [For more details, see Methodology appendix]

The estimates are not designed to explain why the net growth rate has declined. There could be a number of possible causes, including a slowdown in U.S. economic growth that has had a disproportionate impact on foreign-born Latino workers,¹ at the same time that economic growth in Mexico and other Latin American countries has been stable. Another factor could be a heightened focus on enforcement of immigration laws, which a recent Pew Hispanic Center survey² indicates has generated worry among many Hispanics.

Other major findings:

• Undocumented immigrants make up 30% of the nation's foreign-born population of more than 39 million people. More than four-in-ten of the nation's unauthorized immigrants -- 5.3 million people -- have arrived since the decade began.
• The vast majority of undocumented immigrants -- four-in-five -- come from Latin American countries. In March 2008, 9.6 million unauthorized immigrants from Latin America were living in the United States.
• The number of unauthorized immigrants from Mexico, 7 million, appears to have leveled off since 2007. Mexico remains the birth country of most unauthorized immigrants in the U.S.
• The number of undocumented immigrants from other Latin American nations has fallen since 2007.

Read the full report including a description of the methodology at pewhispanic.org.

Notes

¹ See Latino Labor Report, 2008: Construction Reverses Job Growth for Latinos, June 4, 2008.

² See 2008 National Survey of Latinos: Hispanics See Their Situation in U.S. Deteriorating; Oppose Key Immigration Enforcement Measures, Sept. 18, 2008.