Illegal immigrant population of the United States

Illegal immigrant population of the United States

The actual size and the origin of the illegal immigrant population in the United States is uncertain and difficult to ascertain because of difficulty in accurately counting individuals in this population. National surveys, administrative data and other sources of information provide inaccurate measures of the size of the illegal immigrant population and current estimates based on these data indicate that the current population may range from 7 million to 20 million.

In summary, an estimated 11.5 million unauthorized immigrants were living in US in January 2000 through January 2011.[1] This is a decline from the historic peak of 12.5 million seen in 2007.[2]


  • Size 1
    • Residual method 1.1
    • Remittances to Mexico 1.2
  • Impact of the global financial crisis of 2008–2009 2
  • Origins 3
  • References 4
  • External links 5


Residual method

The “residual method” is widely used to estimate the unauthorized immigrant population of the USA. With this method, the known number of legal immigrants to the United States is subtracted from the reported U.S. Census number of self-proclaimed foreign born people to obtain the total, unauthorized immigrant (residual) population.[3] This methodology is used by the US Department of Homeland Security,[4] the Pew Hispanic Center, the US Census Bureau and others. Since unauthorized immigrants have many reasons for not answering the U.S. Census correctly and since there are no penalties for answering the U.S. Census incorrectly, a direct subtraction is a well-known source of undercount error and has to be corrected. All known users of this methodology correct the foreign born population (about 35–50 million) by 10–40% (3–12 million) to account for this undercount effect. Critics claim this correction is in error no matter which size correction is used.

Using the residual methodology with a minimal 10% foreign born undercount correction (reason for correction size unstated) for the 2000 census, a 700,000 net illegal immigrant increase/year assumption and data from the March 2004 Current Population Survey, Pew estimated that there were 10.3 million illegal immigrants in the USA in 2004. Assuming the same rate of growth, Pew projected this population reached at least 11 million as of March 2005.

The Pew Hispanic Center estimates that, in the 1980s, the net advance of the U.S. illegal immigrant population was at 130,000 per year, increasing to 450,000 per year from 1990 through 1994, further increasing to 750,000 per year from 1995 through 1999, and staying at 700,000–850,000+ per year since about 2000. Illegal Mexican immigration amounts to about 500,000 per year of this influx since about 1999. According to the same Pew Hispanic Center study as of March 2005, the undocumented U.S. population had reached 11 million or more, including more than 6.5 million undocumented Mexicans, which is around 60% of all unauthorized immigrants. Assuming the same rate of growth as in recent years gives around 12 million undocumented immigrants in the United States as of January 2006, increasing at 700,000–850,000 per year—with undocumented Mexicans amounting to about 60%+ (7+ million) of the overall total by 2006. By September 2006, the illegal immigrant U.S. population was thought to be around 13 million. About one-sixth of the illegal immigrant population—about 2.0 million people—is under 18 years of age.[5]

After 2000, the estimation of the growth of the illegal immigrant population becomes more difficult because of a lack of good information. The rate of growth of the illegal immigrant population is estimated with the Consumer Price Survey data from 2004, which suffers from the same under counting problems of the U.S. Census plus the problem of a much smaller statistical sample used (only 10,000–20,000). Its accuracy may well be suspect due to the lack of a truly representative, "random" sample and due to the well-known, non-random distribution of the illegal immigrant population. Again, using these techniques, Pew comes up with around 12+ million U.S. illegal immigrants in January 2006 (with an estimated growth rate of 700,000–850,000 net unauthorized immigrants per year), and this is the "consensus" number used by most reporters. The unstated cumulative error in total U.S. unauthorized immigrants by 2006 could easily be an additional 8 million unauthorized immigrants or more, and the error in the growth rate since 2000 could also be very large but again is unstated by Pew and others. There is a high probability of the U.S. unauthorized immigrant population's size in 2006 being significantly larger than the 12 million predicted as all additional information points to a significant increase (300+%) in the advance rate of illegal immigrants after 2000, not a reduction as initially predicted by Pew.

Investigative journalists Donald L. Barlett and James B. Steele estimated in Time magazine (in its September 12, 2004 issue) that the number of unauthorized immigrants entering into the USA that year would total 3 million – enough to fill 22,000 Boeing 737-700 airliners or 60 flights every day for a year.[6]

In 2006, legal immigrants to the United States numbered approximately 1,000,000 per year - of which about 600,000 were Change of Status immigrants who were already in the USA. Legal immigrants to the United States are now at their highest level ever at over 35,000,000. Net advances by illegal immigrants into the USA have also soared from about 130,000 per year in the 1970s, to 300,000+ per year in the 1980s, to over 500,000 per year in the 1990s, to over 700,000 per year in the 2000s. Total entrance by unauthorized immigrants into the USA may have been as high as 1,500,000 per year in 2006 - with a net of at least 700,000 more unauthorized immigrants arriving each year to join the 12,000,000 to 20,000,000 that are already here in the USA. (Pew Hispanic Data Estimates [1]) [7]

Remittances to Mexico

Bear Stearns' investigators [8] came up with another way to attack this very difficult problem. They made the assumption that the amount of remittances (money sent back to Mexico) is directly proportional to the number of Mexican immigrants in the United States. Other data used for their estimates are the increases of households and school enrollment in Mexican immigrant communities. They conclude that the number of illegal immigrants in the United States may well be twice the official number put out by the U.S. Census of 9 million and may be 20 million people or higher. Information from The Mexican Central Bank details the remittances and shows their growth.[9]

According to that data, remittances stayed fairly stable until 2000 when a steady and dramatic increase began. The change in remittances between 1997 and 1999 is most likely a problem in accounting – the three year average is still about 450 thousand/year consistent with other data. The agreement with the Pew estimate is reasonably good up to 2001 where there is a significant difference – just where the Pew and Census data becomes harder to extrapolate because of lack of good data. Using this technique Bear Sterns investigators come up with a possible illegal population of 20 million or greater. (See figure for calculation) Other data confirming their estimates are the dramatic increases of households and school enrollment in Mexican immigrant communities (read their report for more details). Border Arrest data do not show this dramatic increase in apprehensions.

Critics of this estimate like Jeffrey Passel claim a probable over count by Bear Stearns due to a failure to separate remittances from working class immigrants from funds transfers for real estate purchases and improvement by the affluent. The data used in this section is "Remittances INTO Mexico" and does not accurately represent "Remittances FROM the USA INTO Mexico" as the article would suggest, rather in is the total "Remittances INTO Mexico from ALL other countries".

Impact of the global financial crisis of 2008–2009

The global financial crisis has had a large impact on America. The construction sector and other areas illegal immigrants traditionally seek employment in have shrunk. The recession has also led to a surplus of American labor driving down the benefit of hiring illegal immigrants. It is estimated that over a million illegal immigrants have returned to Mexico since the beginning of the crisis.[10]


According to a Pew Hispanic Center report, Mexicans make up 57 percent of immigrants present in the United States illegally. Another 24 percent are from other Latin American countries. Approximately 9 percent are from Asia, 6 percent from Europe and Canada, with the remaining 4 percent from the rest of the world.[11]

The number of Mexican legal immigrants and Mexican illegal immigrants in the United States has grown quite rapidly over the past 35 years, increasing almost 15-fold from about 760,000 in the 1970 Census to more than 11 million in 2004–an average annual growth rate of more than 8 percent, maintained over more than 3 decades. This remarkable growth has been largely driven by the encroachment of illegal immigrants. On average the net Mexican population living in the United States has grown by at least a half million people a year over the past decade. About 80 to 85 percent of the immigration from Mexico and Central America in recent years has been illegal.[12]


  1. ^
  2. ^ Preston, Julia (July 31, 2008). "Decline Seen in Numbers of People Here Illegally". The New York Times. Retrieved May 5, 2010. 
  3. ^ Jeffrey S. Passel (June 2005). "Unauthorized Migrants: Numbers and Characteristics". Pew Hispanic Center. p. 7. 
  4. ^ MICHAEL HOEFER; CHRISTOPHER CAMPBELL; NANCY RYTINA (January 2005). "Estimates of the Unauthorized Immigrant Population Residing in the United States: May 2006". US Department of Homeland Security, Office of Immigration Statistics, Policy Directorate. 
  5. ^ Jeffrey S. Passel (March 21, 2005). "Estimates of the Size and Characteristics of the Undocumented Population". Pew Hispanic Center. 
  6. ^ DONALD L. BARLETT; JAMES B. STEELE (September 20, 2004). "Who Left the Door Open?". Time. p. 5. 
  7. ^ Steven Malanga (Summer 2006). "How Unskilled Immigrants Hurt Our Economy". 
  8. ^
  9. ^ "CPSS-WB General Principles for International Remittances Services: The Point of View of Authorities: Banco de México". The World Bank. May 2006. 
  10. ^ Preston, Julia (July 31, 2008). "Decline Seen in Numbers of People Here Illegally". The New York Times. Retrieved May 5, 2010. 
  11. ^ Jeffrey S. Passel: Estimates of the Size and Characteristics of the Undocumented Population Pew Hispanic Center, Report March 21, 2005
  12. ^ Jeffrey S. Passel: Estimates of the Size and Characteristics of the Undocumented Population Pew Hispanic Center, Report March 21, 2005, page 2 and figure 4

External links

  • [5] Estimates of the Size and Characteristics of the Undocumented Population
  • [6] A Description of the Immigrant Population
  • [7] Labor Participation less than High School
  • [8] Economy Slowed, But Immigration Didn't
  • [9] Immigration Enforcement Actions: 2004
  • [10] The Labor Force Status of Short-Term Unauthorized Workers
  • [11] Labor Statistics
  • [12] Unauthorized Immigrant Population National and State Trends