This article is excerpted from the PRB Population Bulletin “The American Community Survey” (2005).

(December 2005) The rapid growth of the U.S. Hispanic population during the 1990s was one of the big stories to come out of the 2000 Census. Between 1990 and 2000, the number of Hispanics increased from 22.4 million to 35.3 million, a 58 percent increase. Many states and local areas that had very small Hispanic communities saw those populations increase dramatically during the 1990s. The Hispanic population increased nearly fivefold in North Carolina and at least doubled in 21 other states.1

In many states and local areas, policymakers did not know much about the size or characteristics of the Hispanic population living in their jurisdictions prior to the release of the 2000 Census results. The Census Bureau and other government agencies had underestimated levels of international migration to the United States—primarily from Mexico—during the 1990s, and there were no surveys tracking the size or characteristics of the Hispanic population in local areas.2

By providing updated information about the U.S. population each year, the American Community Survey (ACS)—a relatively new Census Bureau monthly survey that provides reliable and timely demographic, housing, social, and economic data—will greatly improve our understanding of trends in international migration and the characteristics of new immigrants to the United States.3 The ACS questionnaire includes seven questions specific to international migration:

  • State or country of birth;
  • U.S. citizenship status;
  • Year of U.S. entry;
  • Place of residence one year ago;
  • Ancestry or ethnic origin;
  • Language spoken at home; and
  • Hispanic origin.

ACS questions about immigration serve two broad purposes. First, policymakers, researchers, and others use these data to determine the size and characteristics of the foreign-born population in states. For example, these data can help monitor changes in the age, gender, education level, or country of origin of the U.S. foreign-born population, or to develop educational programs for people with limited English skills.

Second, the ACS questions measure the number and destinations of foreign-born individuals entering the United States in a given year. These data help the federal government set and evaluate immigration laws and policies and develop the migration component of annual population estimates.

Fastest-Growing U.S. Foreign-Born Population in the Southern States

The ACS will enhance data on the U.S. foreign-born population from the Census Bureau’s Current Population Survey (CPS) and other sources, with reliable, annual estimates of the foreign-born population in states and local areas.4 The 2003 ACS shows that California has the highest proportion of residents born outside of the United States, at 27 percent, followed by New York (21 percent) and New Jersey (19 percent). The states with the lowest shares of foreign-born residents are located in the South (Alabama, Kentucky, Mississippi, and West Virginia) and in several states in the Great Plains (Montana, North Dakota, South Dakota, and Wyoming) (see figure).5

Percent Foreign-Born by State, 2003

Source: Population Reference Bureau analysis of the 2003 American Community Survey.

But ACS data also revealed that the states with the fastest-growing foreign-born populations between 2000 and 2003 included several Southern states that had relatively small foreign-born populations in 2000 (Arkansas, Kansas, Louisiana, Mississippi, and West Virginia), and two Southwestern states that have historically attracted large numbers of immigrants (Nevada and New Mexico).

Most Foreign-Born Are From Latin America

The ACS also asks respondents to report the U.S. state or foreign country in which they were born, and reports much more detail than the CPS about country and region of birth.6 In 2003, about 52 percent of the U.S. foreign-born population was born in Latin America; 27 percent was born in Asia; 14 percent in Europe (similar to the 2003 CPS findings); 3 percent in Africa, and 3 percent in Canada or Oceania. About 30 percent of all foreign-born residents reported Mexico as their country of origin.

Nearly one-half of the U.S. foreign-born population (49 percent) came to the United States after 1990, and 15 percent arrived between 2000 and 2003. The 2003 ACS revealed that, of the 15 percent of the foreign-born population who arrived after 2000, nearly all (96 percent) lack U.S. citizenship. In Alabama, Mississippi, and Tennessee, nearly one-third of the foreign-born population arrived in this country since 2000, while in New York, only 10 percent did.

A Better Measure of U.S. Immigration Levels

In addition to collecting information about the foreign-born population, the ACS can help measure annual immigration levels to the United States. Unlike the 2000 Census, which asked about place of residence five years ago (in 1995), the ACS requests information about residence in the previous year. Census Bureau staff can therefore use the ACS estimates of new immigrants to help determine the international migration component of official population estimates and projections.7 ACS data for 2000 to 2004 provide reasonable estimates of total immigration levels, and data from the expanded ACS sample will provide detailed information about the characteristics of these new immigrants.

In 2003, 1.5 million people reported in the ACS that they had lived in a foreign country in the previous year—implying they had entered the United States within the last year. This figure is higher than the estimate of new arrivals from abroad measured by the CPS (1.3 million).8 The difference between the two estimates may be due to the different time reference of the surveys: The CPS estimate is based on the population living in the United States in March 2003, while the ACS estimate is an average based on data collected over 12 months.

Both surveys collect information about people entering the United States regardless of their legal status. However, it is likely that they both underestimate the number of unauthorized workers entering the United States. Jeffrey Passel at the Pew Hispanic Center estimates that there are about 10 million undocumented residents in the United States.9 Some foreign-born residents are also excluded from the ACS estimates because they are residing in group quarters, which are not currently included in the ACS sampling frame. The Census Bureau plans to expand the ACS sample to include group quarters.10

Mark Mather is deputy director of Domestic Programs at the Population Reference Bureau. Kerri L. Rivers is a research associate and program administrator for Domestic Programs at the Population Reference Bureau. Linda A. Jacobsen is director of Domestic Programs at the Population Reference Bureau.


  1. U.S. Census Bureau, “The Hispanic Population,” Census 2000 Brief (Washington, DC: U.S. Census Bureau, May 2001): table 2, accessed online at, on May 12, 2005.
  2. The Census Bureau underestimated the U.S. population in 2000 by approximately 7 million people, in part because it had underestimated levels of international migration.
  3. U.S. Census Bureau, “Report 9: Comparing Social Characteristics With Census 2000,” Meeting 21st Century Demographic Data Needs—Implementing the American Community Survey (Washington, DC: Government Printing Office, 2004), accessed online at, on July 19, 2005.
  4. Joseph M. Costanzo, Cynthia J. Davis, and Nolan Malone, “Guide to International Migration Statistics: The Sources, Collection, and Processing of Foreign-Born Population Data at the U.S. Census Bureau,” Population Division Working Paper Series, No. 68 (Washington, DC: U.S. Census Bureau, 2002), accessed online at, on July 19, 2005.
  5. U.S. Census Bureau, “Ranking Tables: 2003—Percent of Population That is Foreign-Born” (2004), accessed online at, on July 19, 2005.
  6. People not reporting a place of birth in the ACS were assigned the state or country of birth of another family member or were allocated the response of another individual with similar characteristics. People born outside the United States were asked to report their place of birth according to current international boundaries. Since numerous changes in boundaries of foreign countries have occurred in the last century, some people may have reported their place of birth in terms of boundaries that existed at the time of their birth or emigration or in accordance with their own national preference.
  7. U.S. Census Bureau, “Table 1. General Mobility, by Region, Sex, and Age: 2003,” Current Population Survey, 2003 Annual Social and Economic Supplement (March 23, 2004 release), accessed online at, on July 19, 2005.
  8. Jeffrey S. Passel, “Estimates of the Size and Characteristics of the Undocumented Population” (Washington, DC: Pew Hispanic Center, 2005): table 1, accessed online at, on May 16, 2005.
  9. Statistics Canada, “Measuring Emigration Through Survey Data: The American Community Survey as a Case Study for Canada,” Working Paper No. 10 (presented at the UNECE/Eurostat Seminar on Migration Statistics, Geneva, March 21-23, 2005), accessed online at, on July 19, 2005.
  10. As part of the federal government’s Fiscal Year 2006 budget, the U.S. Census Bureau has received approximately $170 million to proceed with its plans for the American Community Survey for 2006, including adding group quarters to the survey for the first time. The Census Bureau will also field a Methods Panel in 2006, to evaulate ACS content and determine if any questions need to be modified.