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Immigration in the U.S. Midwest During the 1990s: A Decade of Rapid Change -- Wallace E. Huffman

By Wallace E. Huffman

The First Great Wave of U.S. immigration started in 1890 and continued to 1924 when the National Origins Immigration Policy was enacted. The Second Great Wave of U.S. immigration began in the late 1960s and continues into the 21st century. See figure 1. This wave has been much more concentrated in national origin (Borjas 1994). Borjas suggests that the earlier concept of the U.S. being a “melting pot” has changed to one of the U.S. being a “simmering pot,” new immigrants have been heavily of Mexican origin and given their size, new ethnic enclaves have been formed and old ones expanded. These enclaves have slowed the assimilation process, and they have expanded into rural areas stretching northeast from the U.S.-Mexican border to the Midwest (figure 2).

The objective of this paper is to examine immigration trends and economic impacts for the Midwest over the 1990s, especially for rural and agricultural labor markets, and place them in context relative to changes in California, Florida, and Texas and the whole United States. The paper has the following sections: First, it presents a brief review of U.S and Mexican economic conditions in the 1990s. Second, briefly summarizes the U.S. experience with immigration. Third, an examination of immigration in the 1990s is presented, and then the paper ends with some conclusions.

U.S.-Mexican Macroeconomic Conditions of the 1990’s

Although the U.S. experienced a macroeconomic recession during 1990-92, the period 1992 to 2000 was one of remarkably good economic growth. Mexico also started the decade with much promises, signed the NAFA in 1994 and lower trade barrier more generally in the mid-90s, but thereafter they experienced major macroeconomic instability. The U.S. started the 90s with 3 percent of its labor force employed in agriculture (which was unchanged from 1980), and Mexico started with 28 percent of its labor force in agriculture (which was down from 37 percent in 1989). See the World Bank 1997, pp. 220-21.

For the U.S., the average annual rate of growth of real GDP per capita during the 1990s was 1.9 percent. The average real hourly wage rate of employees in private industry grew at 1 percent per year, which was a reversal of the slow decline over the decade of the 1980s (U.S. President 2003). The male real wage for the 10 percentile (lowest 10 %) peaked in 1973 (Juhn, Murphy, and Pierce, 1993), and then it declined significantly over the next two plus decades. It also declined by 17 percent relative to the male median wage but by 35 percent relative to the 90th percentile. In 1978 the average wage of male high school graduates (and dropouts) relatively to college graduates started declining, and the decline was 35 percent to 1991, and then the rate of decline continued but at a slower pace (Welch 1999). For the decade of the 90s, the U.S. population grew 12 percent (compared to 9 percent for the 80s), and the unemployment ratio was 1.6 percentage point lower in 2000 than in 1990 (U.S. Office of the President 2003).

Real GDP per capita in Mexico grew by 16 percent during the 1990s after declining by about 1 percent over the 1980s. However, real wage wages (in the formal sector) seemed to be more adversely affected; Hanson (2003) reports that Mexican males real wage rate declined 19 percent over the 1990s (for women the real wages were unchanged). The Mexican real wage relative to the U.S. real wage also declined by 17 percent during the 1990s (Hanson 2003). This general deterioration of Mexican labor market conditions during the 90’s occurred in spite of 400,000 Mexicans immigrating to the U.S. annually and relatively large direct foreign investment in Mexico (Hanson 2003).

During the 1990s, Mexico generally lowered trade barriers and investment restrictions on foreign direct investments. New capital flowed heavily into export assembly plants—for apparel, electronics, and autoparts—on the U.S.—Mexican border in the maquiladoras. These maquiladoras are relatively capital intensive and skilled-labor intensive and pay relatively high wage rates, compared to the rest of Mexico (Hanson 2003). By 2000, the maquiladouras accounted for 50 percent of Mexican exports. Real median wage gains occurred during the 1990 in the border industry, but declined elsewhere and the rate of decline grew as the distance from the U.S. border lengthened.

As Mexico trade barriers came down in the 90s, a broad range of goods-producing industries were affected, including low-skilled production goods—t-shirts, footwear, plastics, simple consumer bedrooms. In these areas, Mexico’s comparative advantage deteriorated. It became clear by the late 1990s that Mexico is not competitive worldwide in low-skilled manufactured goods. This is the domain of China and South Asia. Hence, during the 1990s Mexico has experienced growth in the demand for skilled-labor intensive manufacturing near the U.S.-Mexican border and for handling logistics of importing intermediate inputs and exporting output (Hanson 2003). The new economic changes over the 90s, however, have been ones that have caused the market for unskilled Mexican workers to deteriorate, even in the face of signification emigration.

Hanson (2003) also reports high rate of return to schooling in Mexico in 1990 and 2000. The rate of return to 1-4 years of schooling is 10 percent, 5-8 years is 25 percent, 9 years is 40 percent, 10-11 years is 55 percent, and 12 years is 69%. For those with at least some college, the rate of return is even higher – 87% for 13-15 years and 122% for ³16 years in 1990. Furthermore in 2000, the rate of return to college education was about 15 percentage points higher than in 1990. Hence, in Mexico over the decade of the 1990s, the rate of return to college education has risen relative to that for low-educated labor. The 90s have been a period where the disparate between low-skilled and high-skilled Mexican labor increased, and the disparity between U.S. and Mexican real wage rate grew rather than shrink. Hence, there is no indication that the size of the expected return to immigration of low-skilled Mexican labor to the U.S. has declined over the 1990s. In fact, it seems that the differences have widened.

The U.S. Experience with Immigration

In general, the U.S. had a long history of open immigration policy before 1924—virtually no restrictions existed on the number of immigrants from any country. Up to 1924, U.S. immigrants came, however, from Western European countries, which were roughly at a similar stage of economic development as the United States. The first Great Wave of immigrants came during 1880-1924, and although confirmed largely to Western Europeans, it was quite heterogeneous in national origin and language. With the National Origins Immigration Policy in place in the U.S. from 1924 to 1965, new immigrants came largely from Canada and Western Europe (Borjas 1994). During this period, the schooling distribution of immigrants was similar to the distribution of natives (at least for men), and although the average entry wage for new immigrants was roughly 5-8 percent less than for natives, the wage difference could be expected to disappear in the first generation (Borjas 1999).

With the repeal of the National Origins immigration policy, the national-origin mix of immigrants shifted to Latin America (especially Mexico) and Asia (Borjas 1994). These immigrants are largely from low-income and low education countries and heavily Latin American. See figure 3. The outcome has been a rapidly growing disparity in schooling levels of immigrants relative to natives and average entry wage of immigrants relative to the wage rate of natives. These schooling and wage differences have been growing for Mexicans being larger than 40 percent for immigrants after 1980 (see table 1, and Borjas 1999). Furthermore, new immigrants have become increasingly concentrated in their national origin. In 1990, 44 percent of U.S. immigrants were Latin American, largely Mexicans and in 2000, the share was 52 percent (see table1).

With the shift in national-origin mix of immigrants, Mexicans engaging in low cost transnational migration, and new immigrants settling into ethnic enclaves, the rate of assimilation has slowed dramatically (Borjas 1999). Immigrants who are college graduates continue to assimilate relatively rapidly. But assimilation is slower for immigrants who are high school dropouts. Although, legal Mexican immigrants to the U.S. may have slightly more education than native born Mexicans in Mexico (see figure 3), their schooling is far below that of the U.S. native born population.

Although new low skilled undocumented immigrants need assistance for the ethnic enclave to find jobs and housing, the affiliation with a low-educated ethnic enclave means that they do not learn English or other cultural information that would speed up the assimilation process. During the 1980s and 1990s there has been a rise in multiculturalism, which strengthens ties to ethnic groups, especially Latino. This has slowed assimilation and meant that new immigrants and their off-springs experience adverse economic outcomes for at least 2 to 3 generations (and frequently longer) e.g., experience large negative wage differences compared to natives and a very slow and perhaps erratic rate of convergence.

Hence, the economic impact of U.S. immigration can be summarized as follows:

· The relative skills of successive immigrant waves declined over much of the post-war II


· Because the newest immigrant waves start out with such an economic disadvantage and because economic assimilation does not occur rapidly, the earnings of the newest arrivals will remain far below those of natives throughout much of their lives.

· The decline in the relative economic performance of immigrants can be attributed to a single factor, the changing national origin mix of the immigrant population.

· The large-scale migration of less-skilled workers probably had an adverse impact on the economic opportunities of less-skilled natives.

· The new immigrants have relatively high rates of welfare use. As a result, immigration places a substantial fiscal burden on the most affected localities and states.

· There are economic benefits to be gained from immigration, but the net (measurable) benefits are small. The main economic impact of immigration is distributional; immigration redistributes wealth away from workers who compete with immigrants to those who use immigrant services.

· There exists a strong positive correlation between the average skills of ethnic groups in the first and second generations, so the huge skill differentials observed among today’s foreign-born groups will almost certainly become tomorrow’s differences among American-born ethnic groups.

· Ethnic capital, the set of socioeconomic characteristics that characterizes the ethnic group, affects the social mobility of members of that group. These spillovers help explain why ethnic skill differentials tend to persist from generation to generation.

· Ethnic neighborhoods isolate the cultures and attitudes of particular ethnic groups. The ethnic spillovers associated with ethnic capital are mainly transmitted through these ethnic enclaves. (Borjas 1999).

Immigration in the 1990s

Major changes occurred during the decade of the 1990s in the U.S. and in the Midwest in the composition of the population and ethnic composition of employees that affect and reflect the opportunities available to immigrants.

Population. In 1990, eight percent of the U.S. population was foreign born. The foreign born rate for all 12 states in the Midwest was less than the national average (Table 2). Illinois had by far the largest share of foreign born in this region (8.3%) followed by Michigan (3.8%), Minnesota (2.6%), Kansas and Wisconsin (2.5%), Ohio (2.4%), and the other 6 states had less than 2 percent. The foreign born rate is, however, significantly higher in California (21.7%) and Florida (12.9%).

In 2000, the U.S. foreign born share was 3 percentage points higher (11%) and Illinois with 12.5 percent foreign born is the only Midwestern state to have a foreign born rate that exceeds the national average. However, the share of the population that is foreign born rose significantly for all Midwestern states—approximately doubling on average. However, except for Illinois, the largest percentage point increase was in the Southwestern part of the Midwest—and lowest in the northern and eastern part—North Dakota, Wisconsin, Ohio, and Michigan.

Over 1990-2000, the U.S. population increased by 12.4 percent (Table 2). In the Midwest, Minnesota is the state with the largest increase in population (12%). Other states with greater than an 8 percent population growth during the 90s are Illinois, Indiana, Kansas, Missouri, Nebraska, South Dakota, and Wisconsin. Midwestern states with a modest population growth rate of 4-7.9 percent are Iowa and Ohio. North Dakota had a negligible increase. As a comparison, the rate of population growth for Florida and Texas was 21 percent. However in Nevada, Arizona, Colorado, Utah, and Idaho the population growth rate of the 1990s was huge 30 to 66 percent. California, however, has only a 12 percent population growth rate (figure 4).

During the decade of the 90s, the U.S. average rate of growth of the foreign born population was 45 percent. Using this metric, the states of the Midwest have in general a fantastically high rate of growth of the foreign born population—perhaps aided by having a small base and lagging at the beginning. The percentage rate of increase is 75 to 100 percent for Iowa, Kansas, Minnesota, and Nebraska. The rate of increase is 45-74 percent in Illinois, Indiana, Missouri, and South Dakota. The other Midwestern states, however, had 25-44 percent increase in the foreign born population during the decade of the 90s. Furthermore, the rate of population growth during the 1990s in the Midwestern states is positively correlated (about 0.4) with the foreign born share in 1990.

Since the mid-1960s, the share of U.S. immigrants who were of Latin American origin has been increasing (Borjas 1994). In 1990, 44 percent of all U.S. immigrants were from Latin America. For the Midwest, each state in 1990 showed an under representation of Latin- American origin immigrants relative to the U.S. average. Illinois, with 39 percent Latin American origin, had the highest share, but other states with more than 14 percent Latin- American origin were Indiana, Iowa, Kansas, Missouri, Nebraska, and Wisconsin. In 1990 all of the other Midwestern states had less than 10 percent of their immigrant population from Latin America. In contrast, approximately 70 percent of the foreign born in Florida and Texas were from Latin America, and for California, the share was 53 percent.

In 2000, the Latin American share of the U.S. population had increased by 7.3 percentage points (to 51.7%). However for states in the Midwest, there was on average a 12 percentage point increase over 1990 (see Table 2). States with the largest percentage point increase were in the Southwestern part of the Midwest—Iowa, Kansas, Nebraska, but also included Indiana and Wisconsin. States with the lowest percentage point increase were Illinois, Michigan, Ohio, South Dakota, and North Dakota. In comparison, the Latin American share of the foreign born population for California, Florida, and Texas only increased a few percentage points during the 1990s. Figure 5 shows that some counties of the Midwest have experienced very rapid growth in the Latin origin population over 1990 to 2000, e.g., eastern Nebraska, Northwest Iowa, and Southwestern Minnesota. Figures 6 and 7 show, however, that areas where a large number or a large concentration of Latino-origin immigrants reside continue to be located largely in the U.S. Southwest including Southwest Texas and a few other areas with large urban populations—South Florida, Chicago, and New York-New Jersey metro areas. These are the locations of entrenched Hispanic ethnic enclaves.

Historically, the share of the U.S. rural population that is foreign born has been significantly lower than for the urban population (see Figure 1 and Appendix table 1). In 1990 the U.S. rural foreign born share was 2 percent, and it increased to 2.5 percent in 2000 (see Table 3). In 1990 and 2000, all states in the Midwest have a foreign born share of the rural population that is significantly lower than the U.S. average, which in turn is much smaller than the share for California, Florida, and Texas. On average for the states in the Midwest, the rural foreign born share increased by 0.3 percentage points (which is about a 33 percent increase). For example, the rural foreign born share in Iowa, Missouri, and Nebraska almost doubled.

Table 3 also shows that the average rate of decline of the rural population over the 1990s was 3.9 percent. However, in Iowa, Minnesota, Ohio, and South Dakota, the rural population grew during the 1990s by 4 to 8 percent. In Kansas and Wisconsin there was essentially no change, and for the other 7 states, the rural population declined. The decline was quite large in Illinois (-16%), Indiana (-8%), Michigan (-8%), and North Dakota (-5%).

For the U.S., the average rate of growth of rural foreign born during the 1990s was 17 percent (see Table 3). For the Midwest, Iowa, Kansas, Minnesota, Missouri, and Nebraska have growth rates for rural foreign born of 40 to 75 percent. Modest growth rates for rural foreign born occurred in Indiana, South Dakota, and Wisconsin. Little growth in the rural foreign born occurred in Michigan, North Dakota, and Ohio; and Illinois had an 8 percent decline. In California the rural foreign born population also declined, but in Florida and Texas there was growth—8% and 24%, respectively.

Employment. In 2000, the U.S. had a total of about 200 million jobs, and 15 percent (or 29.4 million) of them were in nonmetro areas (see Table 4). The 12 Midwestern states accounted for about one-third of the U.S. total rural nonmetro jobs in 2000. Ohio had 1.1 million nonmetro jobs in 2000, and Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin have roughly 1 million. Kansas had 0.7 million, Nebraska 0.5 million, South Dakota 0.3 million, and North Dakota 0.2 million. In contrast, California and Florida had about 0.5 million nonmetro jobs, but Texas has 1.6 million. Hence, the Midwest is a major player in the nonmetro labor market.

Employment in farm and farm related jobs can be subcategorized into production (on farm), farm inputs, farm related processing and marketing, and farm related wholesale and retail trades. In 1997, 15 percent of all U.S. jobs were in farm and farm related jobs, with 2 percent of the jobs in production, 0.3 percent in farm inputs, 2.0 percent in farm related processing and marketing, and 10 percent in farm related wholesale and retail trade (see Table 4). In the Midwestern states, Illinois and Michigan had less than 15 percent of their jobs in the broad class of employment, but all other states had a larger share of jobs in farm and farm related employment. For Iowa, Nebraska, North Dakota, and South Dakota the share is a little over 20 percent. For the other six states, the farm and farm related employment share is 15-19.9 percent.

In contrast, California, Florida, and Texas had about 14 percent of all jobs in farm and farm related work.

The (on-farm) production-job share is relatively large in Iowa (6%), Kansas (5%), Nebraska (6%), North Dakota (9%), and South Dakota (8%), but smaller in other Midwestern states and in California, Florida, and Texas (1.2-1.6%). Iowa, Nebraska, North Dakota, and South Dakota have a relatively large share of jobs in farm inputs (1.6-1.9) and in farm related processing and marketing (2.3-4.0%). The share of the jobs in farm related wholesale and retail trades is approximately 10 percent for the U.S., each state in the Midwest, and for California, Florida, and Texas.

Nonmetro jobs are relatively concentrated in farm and farm related jobs (see Table 4). Nationally 23 percent of all nonmetro jobs in 1997 are in farm and farm related jobs, 7 percent as in (on-farm) production, 0.8 percent in farm inputs, 3.9 percent in farm related processing and marketing, and 9.9 percent in farm related wholesale and retail trade. In the Midwest, Iowa, Kansas, Minnesota, Missouri, Nebraska, North-Dakota, and South Dakota, have more than one-fourth of their nonmetro jobs in farm and farm related employment. The other four Midwestern states have 17-24 percent of their nonmetro jobs in this area. As a comparison, 22-27 percent of the nonmetro jobs in California, Florida, and Texas are in farm and farm related employment.

For non-metro jobs, (on-farm) production and farm related wholesale and retail trades employment accounted for a relatively large share---about 10 percent or more in Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, and South Dakota (see Table 4). The production share in the nonmetro jobs is significantly low in the other Midwestern states, and is California and Florida, but it is 13 percent in Texas.

The U.S. on-farms production employment consists of farm operators and unpaid family labor, hired farm workers, and contract farm labor (Oliveria and Cox 1984). Data for farm contract labor are available in the National Agricultural Workers Survey (NAWS). See Mines 2002. The USDA produces estimates of the hired farm work force component of all farm labor. These data for 1987 and 1998 are summarized for the U.S., and four major production regions, in table 5.

These data (in table 5) show that there were 2.7 million U.S. hired farm works in 1987, which is immediately after the Immigration Reform and Control Act of 1986. They were distributed as follows: 16 percent in the West, 42 percent in the Midwest, 32 percent in the South and 9 percent in the Northeast (see Table 5). Over the next 12 years the size of the U.S. farm hired work force fell by compound rate of 10 percent per year. The much smaller hired farm work force was allocated 42 percent to the West, 19 percent to the Midwest, 31 percent to the South, and 7 percent to the Northeast. Hence, there was a major reallocation of hired farm workers toward the West and away from the Midwest over this period.

In 1987, a majority of hired farm workers were engaged in livestock production. This had changed by 1998, when a majority were employed in crop production. The main reallocation was away from livestock production (see Table 5). This shift in type of farm production work was more pronounced in the West—a 27 percentage point gain for crop production—and South, but in the Midwest the adjustment went in the opposite direction—from 47 percent in crop production in 1987 to only 24 percent in 1998. These sharply contrasting adjustments in the Midwest and West reflect the dramatic shift to no-till, chemically- and mechanically-intensive farming over the period in the Midwest and growing demand for labor-intensive fresh fruits and vegetables produce in the West (Mines 2002, Huffman 2002, Gardner 2002).

Some of the demographic attributes of the hired farm workers have changed over the 90s. For the U.S. and all regions except the Northeast, the gender composition became more heavily dominated by males (see Table 5). In 1987, 92 percent of the hired farm work force was white (not Hispanic) and only 3 percent were Hispanic. In contrast, in 1998, 42 percent of the hired farm workforce were Hispanic. In the West and South, there was a dramatic increase from 1987 to 1998 in the share that is Hispanic—from 4 percent to 69 percent in the West and from 1 percent to 37 percent in the South. In the Midwest, the Hispanic share of the hired farm work force increased only 3 percentage points, and for the Northeast, the share of Hispanic seems to have declined. (See Table 5).

According to the USDA data, hired farm workers are concentrated in the 25-44 age group, and 39 percent were in this age group in1987, and it increased to 47 percent in 1998. In the West, South, and Northeast there were similar percentage increases in the share of the hired farm work force over 1987 to1998. However in the Midwest, there was a major shift in composition to workers who were less than 20 years of age (see Table 5).

In 1987, when the U.S. hired farm work force was 92 percent white, 80 percent of the workers had 12 or more years of schooling. In contract in 1998 after the Hispanic share had risen dramatically, only 43 percent of hired farm works had 12 or more years of schooling (table 5). The share with 8 years or less of schooling increased from 11 percent in 1987 to 33 percent in 1998. In all regions, the share with 12 or more years of schooling declined sharply between 1987 and 1998—to 60 percent in the Midwest and Northeast, 26 percent in the West, and 42 percent in the South. Hence, the most dramatic decline in schooling (and skill) levels of the hired farm work force over the 1990s seems to have occurred in the West. Hence, over this 12 year period, the average skill level of the U.S. hired farm work force has declined dramatically.

Discussion. The evidence that I have presented has shown that population growth in the Midwest during the 90s—total and rural-- has been negatively related to share of foreign born in 1990 and positively related to the immigration rate after 1990. Because the region as a whole was lagging in 1990, it had the opportunity for an unusually high rate of growth of all foreign born and foreign born who were Latin American in origin. In this sense the Midwest has caught up during the 90s. Some of these immigrants were absorbed into nonagricultural employment and others were drawn into farm and farm-related employment.

The evidence for agricultural employment, either as hired farm workers or contract farm labor, is that Mexicans average less than 8 years of schooling. This is far below the U.S. average, and the empirical evidence is that immigrants who have little schooling or come from low-income countries earn far less than native males (see figure 8) and the size of the differential has been rising during the 1990s. Furthermore, the empirical evidence is that new immigrants with these attributes can be expected to assimilate very slowly, taking several generations. Furthermore, if there are positive spillover effects locally associated with an educated population (Moretti 2003; Carneiro and Heckman 2003), a large influx of low-schooled Mexican immigrants will lower the average level of schooling almost everywhere in the Midwest and may have negative consequences for the local crime rate, civic service, public school quality, and quality of public goods supplied by the community. Furthermore, Carneiro and Heckman (2003) argue that it is a very high rate of return to non-cognitive learning of pre-school age children and the effects are long term. This type of early child activity could be used to speed up the assimilation process for children of immigrants. These are issues that state governors and city mayors some consider seriously as they purse different growth possibilities and strategies in the early part of the 21st century.

Given that a large share of new immigrants to the Midwest are Mexican, and they have taken up residence in areas which might be called new ethnic enclaves, this promises to slow their assimilation. However, it may be a blessing in disguise that the immigrants have come to the Midwest, where ethnic enclaves are generally less entranced than in South Texas, Southern California, and South Florida. Although they made obtain few benefits early in the immigration experience they may be less tightly attached to the enclave in the Midwest (excluding the Chicago area) and over the long-run they may be able to obtain full time jobs and learn English relatively quickly, e.g., in one generation.


This paper has presented an examination of the immigration trends and economic impacts for the Midwest over the 1990s. It has been a period of dramatic change, and it seems likely that the new immigrants will be involved in an assimilation process that will require several generations, rather than one, and be perhaps erratic. New Mexican immigrants and their off-spring will not quickly melt into the native born population and workforce.

The United States should give serious consideration to establishing a new immigration policy built upon a point system similar to that of Canada and a few other countries. In this system, individuals who know English, have high levels of education, have education in shortage areas, and can bring large financial resources would be given the opportunity to immigrate. This new point system would change dramatically the composition of legal immigration. Undocumented Mexican immigrants, however, would continue to be a significant problem, but potential progress could be made here with a stream-lined temporary guest-worker program.


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