Editor's note: For updated numbers on the unauthorized population in the United States, please see Unauthorized Migrants Living in the United States: A Mid-Decade Portrait.
About 5.3 million undocumented immigrants from Mexico are living in the United States, according to estimates based on the March 2002 Current Population Survey (CPS) as well as census and other government data. Over one in every two Mexican immigrants is undocumented, compared with about one in every six for the remainder of the foreign born.
Mexican Immigration to the United States
Mexico represents the largest source of immigration to the United States. Of the 32.5 million foreign born covered in the March 2002 CPS, 9.8 million or 30 percent were from Mexico; the next largest source, the Philippines, accounted for only one-seventh as many at 1.4 million. The rest of Latin America accounted for 7.3 million or 23 percent. Asian immigrants, at 8.5 million, made up 26 percent of the total foreign-born population. There were 5.4 million foreign born from Europe and Canada, accounting for 17 percent of all immigrants. Africa and the remaining countries, at 1.4 million, made up four percent of all foreign born. (see maps of foreign born in the United States)
Mexican immigrants account for about one-fifth of the legal immigrants living in the United States. This large percentage is actually a legacy of the legalization programs of the Immigration Reform and Control Act of 1986 (IRCA), under which about two million formerly undocumented Mexicans acquired legal status. In terms of the annual inflow of legal immigrants, about one in seven are Mexican. This share is substantially larger than the legal flow from any other country.
Mexico is also the single largest source of undocumented immigrants. There were an estimated 9.3 million undocumented immigrants in the United States as of March 2002. Note that this estimate encompasses those included in the March 2002 CPS plus an allowance for those missed. Of these, about 5.3 million or 57 percent were from Mexico. The rest of Latin America (mainly Central America) accounts for another two million or just under 25 percent. Asia at about 0.9 million represents 10 percent. Europe and Canada together account for about five percent, as do Africa and the rest of the world (see Figure 1).
Growth of the Mexican-Born Population
While the Mexican-born population in the United States has grown substantially since 1990, the undocumented population from Mexico has increased even faster. The 1990 Census included 4.3 million immigrants from Mexico. By 2000, this population more than doubled to 9.2 million with a further increase to 9.8 million in 2002. The undocumented population from Mexico increased from two million in 1990 to 4.8 million in 2000 and to 5.3 million in 2002. Thus, between 1990 and 2002, the undocumented population from Mexico increased by about 250,000 to 300,000 per year on average; evidence from successive CPSs suggests that the annual inflows increased dramatically around 1997 or 1998.
The undocumented from Mexico have become an increasingly larger part of the total Mexican immigrant population. Between 1990 and 2002, the legal population from Mexico roughly doubled while the undocumented population grew by 165 percent. As a consequence, the proportion of undocumented among Mexican immigrants living in the country increased from approximately 47 percent to about 54 percent by 2002. This increase has occurred because a very large proportion of all new immigrants from Mexico are undocumented. Of all Mexicans who came to the United States since 1990, more than four of every five remained undocumented by 2002. Among those who entered in the 1980s, only about one in five is still undocumented.
In fact, a very large majority of the Mexican immigrants arriving in the 1980s were undocumented when they came, but most had acquired legal status by 2002. This pattern of new flows was largely undocumented, while the fact that those Mexicans who had resided in the U.S. for a decade or more had managed to become legal was found in analyses of the 1980 Census, the 1990 Census, and CPS data from the 1990s.
New Mexican Immigration Growth Centers
New destinations for Mexican immigrants emerged in the late 1990s. The four states with the largest Mexican immigrant populations—the traditional settlement areas of California, Texas, Illinois, and Arizona—continued to attract migrants, but a much larger share went to new destinations. The share of Mexican immigrants residing in these four states dropped from 89 percent in 1990 to 72 percent in 2002, while the number residing in these states increased by 87 percent from 3.8 million to 7.1 million.
At the same time, Mexican immigrants moved out of these states, especially California, both to nearby states and totally new settlement areas in other parts of the country. The share of new immigrants from Mexico going to these non-traditional settlement areas greatly increased. Mexican immigrants moved to the southeastern part of the country, including Alabama, Arkansas, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, and Tennessee, for jobs in poultry processing, light manufacturing, and construction. In the upper Midwest, including Iowa, Nebraska, Minnesota, and Wisconsin, Mexican immigrants took jobs in pork, beef, and turkey processing. Two additional southern states, Delaware and Maryland, and the western states of Colorado and Utah, also experienced rapid growth in their Mexican-born populations between 1990 and 2000. All together, the Mexican immigrant population outside the four largest states increased more than five-fold between 1990 and 2002 from about 500,000 to 2.7 million. (see state data map)
The new destination states for Mexicans have very large proportions of recent arrivals from abroad. While detailed data on the distribution of the undocumented population from Mexico are not available, it appears that a very large share of the immigrants in these states are undocumented. In most of the new destinations between one-third and one-half of the total foreign born are undocumented. Between 40 to 49 percent of all immigrants in Arkansas, Colorado, Georgia, Nebraska, North Carolina, and Utah are undocumented, while between 30 and 39 percent in Alabama, Iowa, Kentucky, Tennessee, Mississippi, South Carolina, and Wisconsin are undocumented. In contrast, only about one-quarter of the immigrants in California and Illinois are undocumented.
In summary, migration from Mexico to the United States has accelerated rapidly to the point where about nine percent of the population born in Mexico is now living in the United States. While a large majority (around 80 percent) of all newly arrived immigrants from Mexico are undocumented, only about half of all Mexicans in the United States are undocumented. And while average annual flows from Mexico since 2000 are slightly smaller than in the late 1990s, they remain large and above the levels of the early 1990s. More importantly, immigration from Mexico shows no sign of dropping significantly in the near future, even in the face of post-September 11 security measures and a weakening economy. This continued migration is facilitated by the geographic dispersal of the flow within the United States as more economic niches become available to the newly arriving migrants.
Barring major changes in the nation's legal immigration policy, its enforcement strategies, or a sustained deterioration in the economy, it is likely that overall migration and migration from Mexico in particular will continue at roughly current levels. Thus, the United States can anticipate the entry of another 14 million immigrants between 2000 and 2010 with net migration of at least 400,000 Mexicans per year. Under these assumptions, the foreign-born population would increase from 31 million in 2000 to about 40 million in 2010, to represent 13 percent of the total population. The Mexican-born population would grow from about nine million in 2000 to almost 13 million in 2010; at that point, more than 10 percent of the Mexican-born population would be in the United States with less than 90 percent in Mexico.