[20070124]RS21938_在美国未经授权的外国人：1986年以来的估计数.pdf

Order Code RS21938Updated January 24, 2007Unauthorized Aliens in the United States:Estimates Since 1986Ruth Ellen WasemSpecialist in Immigration PolicyDomestic Social Policy DivisionSummaryEstimates derived from the March Supplement of the U.S. Census Bureaus CurrentPopulation Survey indicate that the unauthorized resident alien population (commonlyreferred to as illegal aliens) has risen from 3.2 million in 1986 to 10.3 million in 2004.The estimated number of unauthorized aliens had dropped to 1.9 million in 1988following passage of a law that legalized many unauthorized aliens. Research suggeststhat a constellation of factors has contributed to the increase in unauthorized residentaliens, including the “push-pull” of a prosperous economy, the inadvertent consequenceof border enforcement policies that have curbed the fluid movement of migrant workers,and the backlogs in processing immigrant petitions. Some observers also assert thatresources for enforcement of immigration laws in the interior of the country areinadequate. This report does not track legislation and will be updated as needed.BackgroundAn estimated 35.7 million foreign-born people resided in the United States in 2004