No. 76 March 2013
Measuring Immigrant Assimilation in
Jacob L. Vigdor, Adjunct Fellow, Manhattan Institute for Policy Research
This report is the fourth in a series of examinations of immigrant assimilation in the United States. It introduces evidence derived from the American Community Surveys of 2010 and 2011. This new information extends a database on the status of immigrants in the United States that goes back to 1900, and provides detailed information for the period since 1980. The new data provide a more complete picture of changes in the immigrant population occurring after the onset of the “Great Recession” in 2007.
The report uses the assimilation index, a summary measure of the degree of similarity or difference between the foreign- and native-born populations in the United States. The assimilation index is computed using three sets of factors: economic (including employment and education indicators), cultural (including English language ability and intermarriage), and civic (including citizenship and military service). The report provides information on a composite index incorporating all three sets of factors, and component indices examining one set each. The major findings are as follows:
The immigrant population has shifted dramatically since the recession. Migration rates from Mexico have been very slow for the past five years, while rates from other parts of the world—notably Asia—have quickened.
Between 2006 and 2011, overall immigration from Asia has seen a net increase of 1.4 million people. This includes major cohorts from mainland China and Vietnam as well as English-speaking countries such as India and the Philippines.
By 2011, the total number of Mexican immigrants and the total number of immigrants from all Asian countries were roughly equal. In 2007, Mexican immigrants exceeded the number of Asian immigrants by 1.5 million.
Immigrants are now more assimilated, on average, than at any point since the 1980s. The rise in assimilation can be attributed to this slowdown and shift in the arrival rate of new immigrants. The rise in assimilation has been most apparent along cultural and civic dimensions.
The immigrant population shows signs of recovering from the recession. Economic assimilation declined as growth slowed, but has regained its pre-recession level.
Post-recession immigrants are more assimilated than those who arrived before the recession. In general, more recently arrived immigrants tend to be less assimilated. In a stark reversal of this historical pattern, post-recession immigrants are more culturally and economically similar to natives than immigrants arriving as much as a decade earlier.
The bursting of the housing bubble played a role in increasing assimilation. Metro areas with the largest increases in immigrant assimilation tend to be those that were most affected by the housing boom-and-bust cycle. The evaporation of easy mortgage credit and construction-related jobs likely reversed the flow of new immigrants to these areas.
The near disappearance of newly arrived, un-assimilated immigrants from American soil may help to explain why initiatives to reform immigration policy have gained traction this year. Since the colonial era, backlash against immigration has focused on cultural and economic differences between immigrants and natives; this report demonstrates that these differences are now less noticeable than they have been in a generation.
The report provides a complete set of assimilation index values for immigrants by country of origin and metropolitan area of residence.
About the Author
Jacob Vigdor is an adjunct fellow at the Manhattan Institute, a professor of economics and public policy at Duke University’s Sanford School of Public Policy, and a research associate at the National Bureau of Economic Research. He received a B.S. in policy analysis from Cornell University in 1994 and a Ph.D. in economics from Harvard University in 1999. His research interests are in the broad areas of education policy, immigration policy, housing policy, and political economy. Within those areas, he has published numerous scholarly articles on the topics of residential segregation, immigrant assimilation, housing affordability, the consequences of gentrification, the determinants of student achievement in elementary and secondary school, the causes and consequences of delinquent behavior among adolescents, teacher turnover, civic participation and voting patterns, and racial inequality in the labor market. These articles have been published in outlets such as The Journal of Political Economy, The Review of Economics and Statistics, The Journal of Public Economics, The Journal of Human Resources, and The Journal of Policy Analysis and Management. Vigdor has taught at Duke since 1999. His book on assimilation and immigration policy, From Immigrants to Americans: The Rise and Fall of Fitting In, published by Rowman and Littlefield in the fall of 2009, received the 2009 IPUMS research award for the best analysis of historical Census data.
The so-called “Great Recession” of 2007–09 occasioned a pause in migration to the United States. For the first time in at least a generation, the foreign-born population declined between 2007 and 2008. Since this temporary drop, immigration has resumed, albeit at a slower pace. Between 1990 and 2007, the foreign-born population increased by more than 1 million per year. Over the past five years, this rate has been cut in half. Nonetheless, Census Bureau statistics show that the foreign-born population has crossed a major milestone—the 40-million mark—for the first time in American history.
This report extends a series of prior studies of immigrant assimilation in the United States, using data collected by the Census Bureau in 2010 and 2011. For the purposes of this report, assimilation is defined as a process whereby the distinctions between foreign- and native-born residents of the United States become less noticeable as foreigners spend more time in the country. The report’s main indicator, the Assimilation Index, summarizes the state of this process at a given point in time. The index factors in a range of economic, civic, and cultural indicators. It can be computed for the foreign-born population as a whole, for individual immigrant groups, for migrants living in particular regions of the United States, and for immigrants who have spent a fixed amount of time in this country. The index can be computed using only one set of indicators—economic, civic, or cultural—or all three simultaneously.
Complete technical details regarding the computation of the assimilation index can be found in earlier reports. The methodology remains unchanged. Essentially, the index is computed first by constructing a statistical algorithm for predicting whether an individual is native-born or foreign-born, as a function of economic, civic, and cultural indicators.
Economic assimilation describes the extent to which immigrants, or groups of immigrants, make productive contributions to society indistinguishable in aggregate from the contributions of the native-born. Economic assimilation is low when immigrants cluster at certain points on the economic ladder—most notably, the low-skilled rungs—and high when their distribution on the economic ladder matches that of native-born Americans.
The economic assimilation index is particularly relevant to two major areas of policy debate: the impact of immigration on the labor market; and the fiscal impact of immigration. A simple calculation suggests that immigrant participation in the labor market generates net benefits, through lower consumer prices and higher shareholder returns, of $50 billion per year. But such benefits are accompanied by reductions in wages for native workers competing in the same market. It has also been argued that the immigration of highly skilled, entrepreneurial workers creates new jobs.] The economic assimilation index can help track whether the skills of immigrants are matched to or mismatched with those of native workers.
From a fiscal perspective, the economic assimilation index reveals information that can potentially address concerns that immigrants take up welfare benefits at disproportionate rates or rely on charitable provision of health care. Economic assimilation also correlates with immigrants’ contributions to the Social Security and Medicare trust funds and may help determine the impact of immigrants’ housing demand on property values and local property tax revenues.
The following factors are used to measure economic assimilation:
- Earned income in the year prior to the survey (not available for 1900–1930)
- Labor-force participation
- Unemployment (not available for 1900–1930)
- A quantitative ranking of occupations by average income in that occupation in 1950
- Educational attainment (not available for 1900–1930)
- Home ownership (not available for 1900–1930)
Since the labor-force participation and earnings patterns of males and females have historically been quite distinct, the index measures the immigrant-native differences in these factors separately by gender.
Cultural assimilation is the extent to which immigrants, or groups of immigrants, adopt customs and practices indistinguishable in aggregate from those of the native-born. Factors considered in the measurement of cultural assimilation include intermarriage and the ability to speak English, which have been the focus of many previous efforts to track immigrant assimilation in the United States. Cultural assimilation also incorporates information on marital status and childbearing. It is important to note that cultural assimilation is not a measure of a group’s conformity with any preconceived ideal. Changes in the customs and practices of the native-born can promote cultural assimilation just as easily as changes among the foreign-born.
Some of the most spirited charges in immigration policy debates concern the cultural aspects of immigrants’ integration into American society. While some aspects of this debate, such as the value of traditional American culture, are relatively abstract, other aspects are very concrete. State and local governments, for example, often face cost burdens associated with providing services—most notably, public education—to non-English-speaking immigrant groups. Incorporating childbearing patterns into the index allows it to measure the potential impact of immigration on public schools in the near term, and on broader fiscal issues in the long term. Marital patterns, including the decision to marry a native-born spouse, or the decision to reside in the United States without one’s spouse, provide clues as to immigrants’ long-term intentions, which are critical to understanding the long-term fiscal impact of immigration.
The following factors are used to measure cultural assimilation:
- Ability to speak English
- Intermarriage (whether an individual’s spouse is native-born)
- Number of children
- Marital status
Civic assimilation is a measure of immigrants’ formal participation in American society, primarily through naturalization. Since native-born residents of the United States are citizens by default, civic assimilation increases as the proportion of immigrants who are naturalized citizens increases. The index of civic assimilation also incorporates information on past or present military service, except in the years from 1900 to 1930. Since military service is more common among males than females, the index measures the immigrant-native difference separately by gender. Both naturalization and military service are signals of a strong commitment to the United States—though the power of these signals is directly influenced by government policy. The government sets standards for naturalization and, to some extent, determines the benefits of naturalization, by setting differential policies for citizens and noncitizens; military recruitment needs determine the number of opportunities for service in the armed forces. Changes in civic assimilation could, in theory, reflect either changes in immigrant civic attitudes or changes—perhaps even anticipated changes—in policy. It is important to note that the Census Bureau collects no information on immigrants’ legal status, which means that this study cannot use legal status as a factor in the computation of civic assimilation.
The following factors are used to measure civic assimilation:
- Military service
To some extent, civic assimilation is an even stronger indicator of immigrants’ intentions than cultural assimilation. The choice to become a naturalized citizen, or to serve in the United States military, shows a tangible dedication to this country. Civic assimilation may thus forecast the long-run impact of immigration, both in a concrete fiscal sense and in a more abstract cultural sense.
When immigrants and natives are very similar, this algorithm will not perform much better than random guessing. When the two populations are distinct, the algorithm will have better success. The assimilation index is a measure of how successful this algorithm is, on average. The index returns a value of zero when immigrants and natives are perfectly distinct from one another. It returns a value of 100 when the two groups are indistinguishable.
Setting the Scene
Figure 1 traces the growth of the foreign-born population of the United States from 1960 through 2011. The drop in foreign-born population from 2007 to 2008 was small in absolute terms—only 100,000 out of 38 million, according to Census estimates—but a symbolically significant break in a very long trend. Moreover, immigration in the post-recession years has continued at a slower pace. The number of Mexican-born immigrants in 2011 remained below the 2007 peak. Immigration after 2007 has been dominated by migrants from Asia (a net increase of 1.4 million) and more distant parts of Latin America (a net increase of 850,000). In 2007, the number of Mexican immigrants exceeded the number of immigrants from all Asian countries by 1.5 million. By 2011, the two groups were of roughly equal size.
The slowdown in the arrival rate of new immigrants and the shift in migrant flows away from Mexico portend important changes in the overall assimilation of the foreign-born population. Newly arrived immigrants are the least assimilated, and with fewer of them around, the average level of assimilation is bound to increase.
Moreover, immigrants from Mexico and nearby countries in Central America have been the least assimilated groups in recent decades. The shorter distances involved in moving across the border, rather than across an ocean, make it easy for families with little education or wealth to make the move. The 2011 assimilation index report showed that Latin American immigrants in Spain, for example, are much more assimilated than their North American counterparts. Similarly, North African immigrants in the United States are more assimilated than North Africans in Europe. The lack of legal status among many Mexican and Central American immigrants reduces both their ability and incentive to assimilate into the mainstream. Immigrants without legal status have limited employment options and no path toward citizenship. The uncertain duration of their stay in the country reduces their incentive to learn English or undertake other costly actions that pay off in the long run.
The notion that recession-induced changes in migration patterns would lead to an increase in immigrant assimilation was confirmed in the 2009 assimilation index report. This report introduces data from 2010 and 2011, bringing the time series well into the post-recession period.
Assimilation at its highest level in decades
Figure 2 displays the long-term trends in the assimilation index from 1980 to 2011. The figure shows trends in the composite assimilation index, which incorporates data on economic, civic, and cultural indicators, and component indices that consider sets of indicators in isolation. The composite index is always lower than the components. Logically, the algorithm used to predict whether an individual is native- or foreign-born is always more effective when it uses more information. The composite index uses the most information.
All measures, the composite and all components, have shown an increase in recent years. These trends are most obvious using cultural and civic indicators. Since the onset of recession, these two indices have increased steadily. The economic assimilation index, by contrast, fell during the recession, underscoring the particular vulnerability of immigrant families in the American economy. Economic assimilation shows an uptick, however, in the most recent data. The composite index now stands at 30, after spending more than two decades in the 20s.
All four measures now stand at levels that have not been exceeded since the 1980s. The degree of similarity between the foreign- and native-born populations is now higher than it has been in a generation.
Understanding the increase
In theory, the rise in the assimilation index could reflect changes in the assimilation process, or changes in the set of immigrants undergoing it. Figure 3 begins to help us understand how and why the change has occurred. It shows information on the assimilation of newly arrived immigrants—those entering the country within the past five years—at points in time between 1900 and 2011, using a specialized version of the assimilation index that permits comparisons over this period of eleven decades. The UnitedStates experienced significant migration waves at both the beginning and end of the twentieth century. During both periods—between 1900 and 1920, and again between 1980 and 2000—the assimilation level of new arrivals declined. The first immigrants to enter a host country must navigate on their own; they stand to prosper only if they possess the ability to integrate rapidly into the mainstream. Successive waves of immigrants can take advantage of the trail blazed by their predecessors. It is not surprising, then, to see this broad pattern of declining assimilation as immigration waves progress.
After 2000, there is some evidence that the pattern of declining assimilation levels among new arrivals stopped, or even reversed. To be fair, by 2000 the recorded assimilation levels of newly arrived immigrants were extremely low—in the low single digits—and simply could not fall much further. But the reversal is consistent with the observation that migration flows have shifted over the course of the past decade, favoring groups that appear more closely integrated into the mainstream at the point of arrival. At the same time, though, the new arrivals of 2011 were still below those of 1990. The overall increase in assimilation, then, reflects more than a shift in the composition of new arrivals.
Figure 4 provides insight into the process of assimilation over time. It uses data from consecutive Census Bureau surveys to track the progress of synthetic cohorts of immigrants as they spend more time in the United States. Immigrants who arrived in the late 1970s are compared to those arriving in the late 1980s, late 1990s, and the pre- and post-recession portions of the past decade. Consistent with the basic premise that assimilation takes time, each group shows a pattern of steady increases in the assimilation index. This trend occurs for two basic reasons. First, individual immigrants make progress over time—they learn English, obtain better jobs, intermarry, and, in some cases, become citizens. Second, the less-successful exhibit a higher propensity to leave the country. Figure 4 shows the net impact of these two trends and cannot distinguish between them.
Overall, the process of assimilation appears to have changed little over time. Each successive cohort of immigrants begins with assimilation index values in the low single digits, then posts increases to the high teens or low twenties within a decade. Interestingly, in the two oldest cohorts there is some evidence of a stall in the assimilation process after 2000, followed by a resurgence around the time of the recession. This resurgence is explored in some detail below.
Figures 5 through 7 examine cohort progress using the component assimilation indices. Economic assimilation, examined in Figure 5, shows a remarkable finding. The most recent cohort—those arriving since the onset of recession—boasts higher economic assimilation than those arriving just before the recession. This is an unprecedented reversal of a well-established pattern. It largely reflects the shift in composition between cohorts: the pre-recession group includes a large proportion of Mexican immigrants; the post-recession group does not. In economic terms, then, the United States finds itself without a significant group of poorly-assimilated, newly-arrived immigrants for the first time in decades.
The same pattern appears when we examine cultural assimilation. Figure 6 shows the remarkable finding that the post-recession cohort of immigrants is more culturally assimilated than cohorts arriving as much as a decade before them. Even the immediate pre-recession cohort boasts higher cultural assimilation levels than those arriving in the late 1990s. Recalling that the immigrant population dropped slightly in the wake of recession, it would appear that departing migrants were drawn from the less-culturally-assimilated portion of the most recently arrived cohorts. The pre-recession cohort begins, after all, with a typically low cultural assimilation index, but shows unprecedentedly rapid progress over time.
Should Congress and the administration pass an immigration reform bill this year, academic conversation will surely turn to the question of why legislation proved feasible this year after having failed in the past. That the United States has witnessed the near disappearance of newly-arrived culturally and economically distinct migrants might help answer this question. Culturally-based opposition to immigration—among those hoping to preserve English as the nation’s preeminent language, for example, may have softened in part because there are simply fewer migrants with poor language skills than there were a few years ago.
Figure 7 shows that the remarkable inversion of cohort rankings does not extend to the civic assimilation index. The rate of civic assimilation is not governed so much by migration patterns as it is by law. As there have been no significant changes in law over the past decade, it is not surprising that the most recently arrived immigrants—those least likely to qualify for citizenship—remain the least assimilated. The low civic assimilation of new arrivals explains why the composite assimilation of that group remains low.
Civic assimilation patterns among older immigrants—those arriving in the 1980s or earlier—do much to explain the post-recession uptick in composite assimilation rates observed in those cohorts. In recent years, older immigrants have seen little in the way of economic progress, continued cultural assimilation, and a clear renewal of interest in citizenship and other civic indicators.
In the end, then, the evidence indicates that the increase in assimilation largely reflects a shift in migration patterns rather than wholesale changes in behavior. Immigrant groups more disposed to low levels and rates of assimilation have been less likely to enter and remain in the country in recent years. To underscore this point, Figure 8 replicates a figure derived from the first assimilation index report, updated to include the most recent data. It compares the assimilation progress of Mexican and Vietnamese immigrant cohorts. Vietnamese immigrants have been, and continue to be, one of the groups exhibiting the highest rates of assimilation over time; Mexican immigrants lie at the other end of the spectrum. There is no evidence that the average experiences of immigrants belonging to either group have changed much over time. The immigrant population, rather, has shifted towards having a higher proportion of Vietnamese-type immigrants, and fewer Mexican-type immigrants.
Assimilation by country of origin
Figure 9 presents additional detail on assimilation patterns by immigrants’ country of origin. It shows composite assimilation index values for migrants from the ten largest countries of origin as of 2011. A complete list of index values, including component index values, can be found in the appendix to this report.
Among the ten largest groups, four are from Latin America: Mexico, El Salvador, Guatemala, Cuba. With the clear exception of Cuba, these groups are the least assimilated, with index values in the teens, roughly half the overall average for the foreign-born population as a whole. Among Cuban immigrants, assimilation more closely resembles the patterns seen in Asian-origin groups, including migrants from the Philippines, Vietnam, and Korea. All four groups have index values well above the overall average. The country of origin exhibiting the greatest assimilation is, unsurprisingly, Canada.
These patterns across countries of origin have held fairly steady since the first assimilation index report. Figure 10 looks more specifically for evidence of changes in assimilation since the onset of recession. The assimilation index has posted increases of about two points—comparable to the increase observed in the immigrant population as a whole—for the five largest country-of-origin groups, including Mexican immigrants. There has been little change in assimilation among immigrants from El Salvador and Canada. The biggest surprise in this chart pertains to immigrants from Cuba, the only group to post a large decline in assimilation since 2006. The decline most likely reflects the continued arrival of Cuban migrants in the post-recession years—Census estimates indicate that the Cuban-born population has doubled over the past 10 years. This, in turn, most likely reflects the political, rather than economic, impetus for much migration from Cuba. Immigrants seeking jobs are likely to be deterred by a recession; those seeking more fundamental rights or family reunification are not.
Assimilation by Metropolitan Area of Residence
Figure 11 plots composite assimilation index values for the ten metropolitan areas with the largest number of foreign-born residents as of 2011. For the most part, these metro area-specific indices cluster around the national value of 30. The most noteworthy departures from average occur in Houston and the Dallas-Fort Worth metroplex, where assimilation levels fall well below average—in the high teens in the Dallas area. Low assimilation in Texas cities reflects the high concentration of immigrants from Mexico and Central America in that region. Mexican immigrants are also found in significant number in Southern California; the Los Angeles area posts the third-lowest assimilation level among the top ten immigrant destinations. The simultaneous presence of large numbers of Asian immigrants has a moderating effect; in spite of its proximity to the Mexican border, the San Diego metro area posts an assimilation index above the national average. New York and Miami top the list of destination areas with the most assimilated immigrants.
The increase in assimilation observed since the onset of recession in 2007 can be seen in all 10 of these destination areas, as shown in Figure 12. Assimilation has increased most rapidly in the “inland empire” encompassing Riverside and San Bernardino in Southern California. This area was also significantly effected by the bursting of the housing bubble over the same time period. Two other metropolitan areas with significant housing price fluctuations in recent years—Orange County, California and Miami, Florida—have also witnessed large increases in assimilation. In all three areas, the rise in assimilation nearly doubled the rate observed in the nation as a whole.
The rupture of the housing bubble most likely led to increased assimilation largely by affecting the mix of immigrants choosing to live in a metropolitan area. The housing bubble fed a construction boom, and the disappearance of moderately-skilled jobs in the construction industry may have led some immigrants to move on. The subprime mortgage boom that fed the housing bubble may also have played a role. Access to easy credit would have helped low-income immigrants afford homes in these relatively expensive regions. The evaporation of mortgage credit following the housing bust, in turn, would have shut off this access route.
The first Manhattan Institute assimilation index report, issued in 2008, used Census Bureau data through the year 2006 and reported a long period of stability in immigrant assimilation from 1990 through that year. During this period of stability, the steady progress of existing immigrants toward the mainstream was offset by the continued arrival of economically and culturally distinct newcomers.
The five years since that initial report have witnessed a significant disruption of that period of stability. The economic recession and its aftermath have altered the flow of migrants and upended historical patterns of immigrant assimilation. Opposition to immigration reform has traditionally focused on newly arrived, unassimilated, and often undocumented immigrants from Mexico and nearby countries in Central America. This archetype is rapidly vanishing from American soil. The effects of this shift on the average characteristics of immigrants, particularly newly arrived immigrants, are tangible.
There remains some question as to whether the post-recession pattern will persist. Although the United States has officially been in economic recovery since 2009, growth has come slowly, and unemployment rates remain high. The absence of lower-skilled immigrants may reflect this underlying labor market weakness; hypothetically, a decline in unemployment could renew the flow of immigrants across the U.S.-Mexico border.
In the longer run, however, demographic trends raise the possibility that the era of rapid immigration from Mexico is already behind us. The era of intense migration coincides with a period of rapid population growth in Mexico, driven by high fertility rates. As demographers have noted, fertility rates have declined precipitously in Mexico in recent decades, to the point where population growth in that country barely exceeds that in the United States.
While uncertainty remains regarding future immigration trends, it is clear that the demographic environment in the United States is very different than it was prior to the recession. Recognizing and understanding these important shifts will be critical to the formulation of a forward-looking immigration policy.
- Vigdor, Jacob, Measuring Immigrant Assimilation in the United States, Manhattan Institute Civic Report 53, May 2008, http://www.manhattan-institute.org/html/cr_53.htm.
- Vigdor, Jacob, Comparing Immigrant Assimilation in North America and Europe, Manhattan Institute Civic Report 64, May 2011, http://www.manhattan-institute.org/html/cr_64.htm.
- Vigdor, Jacob, Measuring Immigrant Assimilation in the United States, Manhattan Institute Civic Report 59, October 2009, http://www.manhattan-institute.org/html/cr_59.htm.