Mexican Workers in the United States: A Comparison with Workers from Social Security Totalization Countries

CRS Report for Congress
Mexican Workers in the United States:
A Comparison with Workers from
Social Security Totalization Countries
Updated September 6, 2005
Alison Siskin
Analyst in Social Legislation
Domestic Social Policy Division
Gerald Mayer
Economic Analyst
Domestic Social Policy Division


Congressional Research Service ˜ The Library of Congress

Mexican Workers in the United States: A Comparison
with Workers from Social Security Totalization
Countries
Summary
On June 29, 2004, the United States and Mexico signed a Social Security
totalization agreement, the effects of which depend on the yet to be disclosed
language of the agreement. A totalization agreement coordinates the payment of
Social Security taxes and benefits for workers who divide their careers between two
countries. The agreement has not been transmitted to Congress for review, which is
required under law before the agreement can go into effect. This report does not
attempt to estimate the potential cost of a totalization agreement with Mexico, or
reach a conclusion on the effects of such an agreement on U.S. workers and
employers. Instead this report explores one of the issues concerning such an
agreement. Using different socio-economic characteristics, the report compares
persons born in Mexico and living in the United States (both naturalized U.S. citizens
and noncitizens) with persons born in the current totalization countries and living in
the United States.
The Social Security program provides monthly cash benefits to qualified retired
and disabled workers, their dependents, and survivors of deceased workers.
Generally, a worker must have 10 years of Social Security-covered employment to
be eligible for retirement benefits (less time is required for disability and survivor
benefits). Most jobs in the United States are covered under Social Security.
Noncitizens (aliens) who work in Social Security-covered employment must pay
Social Security payroll taxes, including those who are in the United States working
temporarily and those who may be working in the United States without
authorization. There are some exceptions. Generally, the work of aliens who are
citizens of a country with which the United States has a “totalization agreement” is
not covered by Social Security if they work in the United States for less than five
years. In addition, by statute, the work of aliens under certain visa categories is not
covered by Social Security. Currently, since Mexico meets the definition of a “social
insurance country,” a Mexican worker may receive U.S. Social Security benefits
outside the United States. Family members of the Mexican worker must have lived
in the United States for at least five years to receive benefits outside the United
States, but typically under a totalization agreement this requirement is waived.
This report concludes that the Mexican population in the United States has a
different socio-economic profile than both U.S. citizens and persons (both
naturalized U.S. citizens and noncitizens) from current totalization countries.
Workers from totalization countries tend to have more education and higher earnings
than workers born in the United States or in Mexico. Noncitizens from Mexico tend
to be younger and have higher labor force participation rates than naturalized U.S.
citizens from Mexico, and other U.S. citizens. In addition, Mexican noncitizens and
naturalized U.S. citizens from Mexico in the U.S. labor force tend to have more
dependents in their U.S. households. Because Mexican workers may have lower
lifetime earnings, they may receive a higher replacement rate, relative to the payroll
taxes they pay, than workers with higher lifetime earnings, such as U.S. citizens and
noncitizens from the totalization countries. This report will not be updated.



Contents
Overview of Noncitizen Eligibility for Social Security.....................1
Basics of the Social Security Program..............................1
Benefit Formula...........................................2
Noncitizen Eligibility for Social Security...........................3
Totalization Agreements........................................4
Analysis .........................................................5
Overview of Data and Methodology...............................5
Population Characteristics.......................................7
Population ...............................................7
Gender ..................................................7
Age .....................................................8
Education ................................................9
Characteristics of Persons in the Labor Force.......................10
Labor Force Participation Rates..............................10
Unemployment Rates......................................11
Labor Force Participation by Age............................11
Unemployment Rates by Age...............................12
Gender of Persons in the Labor Force.........................13
Disabled Workers.........................................14
Earnings ................................................15
Occupations .............................................16
Full-Time/Part-Time Status.................................19
Arrival Year.............................................20
Dependents ..............................................20
Conclusion ......................................................22
Appendix A: Variation Among the Totalization Countries................23
Brief Overview of Methodology.................................23
Analysis ....................................................23
Population ..............................................23
Age ....................................................23
Education ...............................................25
Labor Force Participation...................................26
Full-Time/Part-Time ......................................27
Arrival .................................................27
Gender .................................................28
Earnings ................................................29
Occupations .............................................30
Appendix B: Data and Detailed Methodology..........................34
Citizenship Variable...........................................34
Confidence Levels............................................35



Figure 1. Distribution of Population by Citizenship Statusand Age,
March 2004..................................................8
Figure 2. Distribution of Population Ages 18 and Over by Citizenship Status and
Educational Attainment, March 2004.............................10
Figure 3. Labor Force Participation Rate and Unemployment Rate by Citizenship
Status, March 2004...........................................11
Figure 4. Labor Force Participation Rate by Age and Citizenship Status,
March 2004.................................................12
Figure 5. Unemployment Rates by Age and Citizenship Status.............13
Figure 6. Gender by Citizenship Status for Those in the Labor Force.........14
Figure 7. Distribution of Employed Persons and Median Earnings by
CitizenshipStatus and Annual Earnings, 2003.......................16
Figure 8. Distribution of Employed Persons by CitizenshipStatus and Full-Time and
Part-Time Employment,March 2004..............................19
Figure 9. Arrival Year for Those in the Labor Force Over Age 16 for Naturalized
U.S. Citizens and Noncitizens from Mexicoand Totalization Countries...20
List of Tables
Table 1. Estimated Resident Population by Citizenship Status and Gender, March
2004 ........................................................7
Table 2. Estimated Percent of Persons Not in the Labor Force Because of a Reported
Disability, by Citizenship Status, March 2004......................15
Table 3. Distribution of Employed Persons by Citizenship Status and Occupation,
March 2004.................................................18
Table 4. Estimated Number of Dependents Residing in the United States Per
Worker, by Citizenship Status, March 2004........................21
Table A1. Estimated Population by Citizenship Status: United States, Mexico, and
Totalization Countries, March 2004..............................24
Table A2. Distribution of Population by Citizenship Status and Age for Select
Totalization Countries, March 2004..............................24
Table A3. Distribution of Population Ages 18 and Over by Citizenship Status and
Educational Attainment for Select Totalization Countries, March 2004...25
Table A4. Labor Force Participation Rate and Unemployment Rate by Citizenship
Status for Select Totalization Countries, March 2004.................26
Table A5. Distribution of Employed Persons by Citizenship Status and Full-Time
and Part-Time Employment for Select Totalization Countries,
March 2004.................................................27
Table A6. Arrival Year by Citizenship Status for Those in the Labor Force for Select
Totalization Countries.........................................28
Table A7. Gender by Citizenship Status for Total Population and Those in the Labor
Force for Select Totalization Countries, March 2004.................29
Table A8. Distribution of Employed Persons by Citizenship Status and Annual
Earnings for Select TotalizationCountries, 2003.....................30
Table A9. Distribution of Naturalized Employed Persons by Occupation by Country
for Select Totalization Countries, March 2004......................32
Table A10. Distribution of Noncitizens Employed Persons by Occupation by
Country for Select Totalization Countries, March 2004...............33



Mexican Workers in the United States:
A Comparison with Workers from Social
Security Totalization Countries
The Social Security Act allows the President to enter into a “totalization”
agreement with another country. For persons who work in one country but are
citizens of another, a totalization agreement coordinates the collection of payroll
taxes and the payment of benefits under each country’s Social Security system. In
June 2004, the Social Security Administration (SSA) signed a totalization agreement
with Mexico. Totalization agreements are subject to congressional review.
Therefore, an issue for Congress is how to respond, if and when the President sends
the agreement to Congress.
Overview of Noncitizen Eligibility for Social
Security1
Basics of the Social Security Program
The Social Security program provides monthly cash benefits to retired and
disabled workers and their dependents, and to the survivors of deceased workers.2
To qualify for benefits, generally workers (whether citizens or noncitizens3) must
work in Social Security covered jobs for 10 years4 (less time is needed for disability
and survivor benefits, depending on the worker’s age). Noncitizens must also meet
other eligibility requirements discussed below.


1For detailed information on social security benefits for noncitizens, see CRS Report
RL32004, Social Security Benefits for Noncitizens: Current Policy and Legislation, by
Dawn Nuschler and Alison Siskin.
2The Social Security program is administered by the Social Security Administration (SSA).
SSA also administers the Supplemental Security Income (SSI) program, a means-tested
entitlement program. Eligibility requirements for noncitizens differ under Social Security
and SSI. For more information on noncitizen eligibility for SSI, see CRS Report RL31114,
Noncitizen Eligibility for Major Federal Public Assistance Programs: Policies and
Legislation, by Ruth Ellen Wasem and Joe Richardson.
3An alien is “any person not a citizen or national of the United States” and is synonymous
with noncitizen. Aliens/noncitizens include persons who are legally present and those who
are in violation of the Immigration and Nationality Act (INA).
4More specifically, to qualify for benefits workers must work in Social Security-covered
jobs for 40 quarters.

The Social Security program is financed primarily by mandatory payroll taxes
levied on wages and self-employment income, which are paid by the worker and the
worker’s employer. Noncitizens, or aliens, who work in Social Security-covered
employment must pay Social Security payroll taxes, including those who are in the
United States working temporarily and those who may be working in the United
States without authorization.5 There are some exceptions.6 Generally, the work of
aliens who are citizens of a country with which the United States has a “totalization
agreement” (see below) is not covered by Social Security if they are sent by a firm
in their home country to work in the United States for fewer than five years. Most
jobs in the United States are covered under Social Security (about 96% of the work
force is required to pay Social Security payroll taxes).7
Benefit Formula. Social Security benefits are computed by applying a benefit
formula to the worker’s lifetime taxable earnings, indexed to reflect the growth in
average wages over time. An average monthly earnings amount (known as the
worker’s Average Indexed Monthly Earnings or AIME) is computed based on the 358
highest years of covered earnings.
The Social Security benefit computation formula is progressive, as it uses “bend
points” to return higher percentages of a lower-wage worker’s lifetime indexed
earnings, computed on a monthly basis. For 2005, the bend points used in the benefit
formula are $627 and $3,779 per month.9 If all or most of a worker’s indexed
earnings fall under the first or second bend point, they will see a higher replacement
rate of average monthly earnings as compared to those whose earnings are above the


5For Social Security payroll taxes to be withheld from wages, a worker must provide a
Social Security Number (SSN) to his/her employer. An alien who is working in the United
States without authorization: (1) may have a valid SSN because he/she worked in the
United States legally and then fell out of status; or (2) may be using a stolen or “bogus”
SSN.
6For example, by statute, the work of aliens under certain visa categories (such as H-2A
agricultural workers, F and M students) is not covered by Social Security.
7In 2005, Social Security-covered workers and their employers each pay 6.2% of earnings
up to $90,000 (this amount is indexed to average wage growth). The self-employed pay
12.4% on net self-employment income up to $90,000, and they may deduct one-half of
payroll taxes from federal income taxes.
8If the worker has fewer than 35 years of covered earnings, zeros are entered in the benefit
formula. The numerator is the sum of the 35 highest years of earnings, indexed to average
wage growth. The denominator is the number of months in the 35-year computation period
(420 months).
9The basic benefit formula for persons or their survivors who become eligible for old-age
insurance or disability insurance benefits in 2005, or who die in 2005 before becoming
eligible for benefits, is: 90% of the first $627 of AIME, plus 32% of AIME over $627
through $3,779, plus 15% of AIME over $3,779. For more information see CRS Report 94-

27, Social Security: Brief Facts and Statistics, by Gary Sidor.



bend points. This is often referred to as the “tilt” in the Social Security benefit
formula. 10
Noncitizen Eligibility for Social Security
Due to a recent change in the law,11 a noncitizen who files an application for
benefits based on a Social Security Number (SSN) assigned on or after January 1,
2004, is required to have work authorization at the time an SSN is assigned, or at
some later time, to gain insured status under the Social Security program. If the
individual was authorized at some point to work in the United states, all of his/her
Social Security-covered earnings will count toward insured status. If the individual
was never authorized to work in the United States, none of his/her earnings will
count toward insured status.12 A noncitizen who files an application for benefits
based on an SSN assigned before January 1, 2004, is not subject to the work
authorization requirement. All of the individual’s Social Security-covered earnings
will count toward insured status, regardless of his/her work authorization status.13
Because Social Security is an earned entitlement program, there are few
restrictions on benefit payments once a worker becomes entitled to benefits.
Nonetheless, noncitizens in the United States must be “lawfully present” to receive
benefits in the United States.14 If a noncitizen is entitled to benefits, but does not
meet the lawful presence requirement, his/her benefits are suspended. In such cases,
a noncitizen may receive benefits while residing outside the United States (including
benefits based on work performed in the United States while the alien lacked
authorization to work) if he/she meets one of the exceptions to the “alien nonpayment
provision.”15 Under the alien nonpayment provision, a noncitizen’s benefits are
suspended if he/she remains outside the United States16 for more than six consecutive


10Although Social Security benefits are not based on a worker’s taxes, a comparison of taxes
paid to benefits received shows that lower-wage earners receive a higher return on their
taxes than higher-wage earners. Similarly, when benefits in the first year of retirement are
compared to a worker’s final earnings, lower-wage earners have a larger percentage of their
earnings replaced by benefits. This so-called “tilt” in the program is deliberate and has
existed since its inception. It is one of the social insurance features of the program,
reflecting the view that Social Security should provide a means through which low wage
workers can sustain at least a “minimal” standard of living in retirement without resorting
to welfare. CRS Report RL31086, Social Security: What Happens to Future Benefit Levels
Under Various Reform Options, by David Koitz, Geoffrey Kollmann, and Dawn Nuschler.
11Social Security Protection Act of 2004 (P.L. 108-203). The act was signed into law on
Mar. 2, 2004.
12Before P.L. 108-203 was enacted all Social Security-covered earnings counted toward
insured status regardless of an alien’s work authorization status.
13For information on P.L. 108-203, see CRS Report RL32089, The Social Security
Protection Act of 2004 (H.R. 743), by Dawn Nuschler.
14Social Security Act §202(y).
15Social Security Act §202(t).
16“Outside the United States” means outside the territorial boundaries of the 50 states, the
(continued...)

months, unless one of several broad exceptions is met. For example, an alien’s
benefits are not suspended if he or she is a citizen or resident of a country with which
the United States has a totalization agreement or a citizen of a country that has a
social insurance or pension system under which benefits are paid to eligible U.S.
citizens who reside outside the country (i.e., a “social insurance country”). Mexico
is a social insurance country.
To receive payments outside the United States, alien dependents and survivors
must have lived in the United States for at least five years previously (lawfully or
unlawfully), and the family relationship to the worker must have existed during that
time. The law provides several broad exceptions to the five-year U.S. residency
requirement. For example, the residency requirement for dependents and survivors
does not apply if the alien is a citizen or resident of a country with which the United
States has a totalization agreement.17
Totalization Agreements
The Social Security Act18 authorizes the President to enter into a totalization
agreement with another country to coordinate the collection of payroll taxes and the
payment of benefits under each country’s Social Security system for workers who
split their careers between the two countries. Without a totalization agreement, an
individual who is sent by a U.S. company to work in a foreign country (and his or her
employer) must contribute to the Social Security systems of both countries, resulting
in dual Social Security coverage and taxation based on the same earnings. In most
cases, totalization agreements allow workers (and their employers) to contribute only
to the foreign system if the worker is employed abroad for five or more years, or only
to the system in their home country if the worker is employed abroad for fewer than
five years.
Totalization agreements also allow workers who divide their careers between
two countries to combine earnings credits under both Social Security systems. Thus,
a worker who may lack sufficient coverage to qualify for benefits under either
program may, under a totalization agreement, qualify for benefits under one or both
systems. The benefits of workers who are allowed to combine earnings credits are
prorated to reflect the number of years the worker paid into each system. The same
treatment applies to foreign workers in the United States.
Since 1978, the United States has entered into totalization agreements with 20
countries:


16(...continued)
District of Columbia, Puerto Rico, the U.S. Virgin Islands, Guam, the Northern Mariana
Islands and American Samoa.
17Social Security regulations (20 C.F.R. 404.1928) specify that a totalization agreement
“may provide that a person entitled to benefits under Title II of the Social Security Act may
receive those benefits while residing in the foreign country party to the agreement,
regardless of the alien non-payment provision.”
18§233.

Australia, Austria, Belgium, Canada, Chile, Finland, France, Germany, Greece,
Ireland, Italy, South Korea, Luxembourg, Netherlands, Norway, Portugal, Spain,
Sweden, Switzerland, and the United Kingdom.
In addition, the United States has signed totalization agreements with Japan
(February 19, 2004) and Mexico (June 29, 2004). Once an agreement is signed it is
sent to the Secretary of State and then to the President for review. The President may
then transmit the agreement to Congress for review. The Social Security Act requires
the President to submit to Congress the text of the agreement and a report on (1) the
estimated number of individuals who would be affected by the agreement and (2) the
estimated financial impact of the agreement on programs established by the Social
Security Act. A totalization agreement automatically goes into effect unless the
House of Representatives or the Senate adopts a resolution of disapproval within 60
session days of the agreement’s transmittal to Congress.19 The agreement with Japan
was transmitted to Congress on November 17, 2004, and according to Congressional
Research Service (CRS) calculations, the 60 session days for congressional action
expired on April 26, 2005. The agreement with Mexico has not been transmitted to
Congress and, reportedly, is still undergoing review at SSA.
Analysis
The remainder of this report uses different socio-economic characteristics to
compare persons born in Mexico and living in the United States with persons born
in the current totalization countries and living in the United States. Individuals born
in Mexico and living in the United States include both naturalized U.S. citizens and
noncitizens. The analysis begins with an overview of selected population and social
characteristics and then focuses on various characteristics of persons in the labor
force.
Overview of Data and Methodology
The data used in this study are from the March 2004 supplement of the Current
Population Survey (CPS), the main source of labor force data for the nation. The
CPS is a household survey conducted by the Census Bureau for the Bureau of Labor
Statistics (BLS). (For a full discussion of the CPS and the methodology, see
Appendix B.) For the purpose of this study, respondents from the current
totalization countries are treated as one group. Luxembourg is not included in the
analysis because the CPS does not have a separate code for that country. Japan is not
included in the analysis because the totalization agreement with Japan has not yet


19It should be noted that the provision of Section 233(e)(2) that allows for the rejection of
a totalization agreement upon adoption of a resolution of disapproval by either House of
Congress is an unconstitutional legislative veto (INS v. Chadha, 462 U.S. 919 (1983)).
Congress has never rejected a totalization agreement. As a result, the fact that the
mechanism under Section 233(e)(2) is unconstitutional has not been an issue. For more
information on the disapproval mechanism. see CRS Report RL32004, Social Security
Benefits for Noncitizens: Current Policy and Legislation, by Dawn Nuschler and Alison
Siskin.

gone into effect. Although the analysis treats individuals from different totalization
countries as one group, there may be differences in socio-economic characteristics
among the countries. This variation is explored in Appendix A for the countries
with large enough samples to be representative.
The comparisons in this report are based on five groups residing in the United
States: (1) U.S. citizens, (2) noncitizens from Mexico, (3) naturalized U.S. citizens
from Mexico,20 (4) noncitizens from totalization countries, and (5) naturalized U.S.21
citizens from the totalization countries. The group of U.S. citizens excludes
naturalized U.S. citizens from Mexico and the current totalization countries.
Although one of the issues surrounding the totalization agreement with Mexico is the
large number of unauthorized Mexicans living in the United States compared to the
unauthorized alien population from the totalization countries, it is not possible, using
CPS data to differentiate between aliens who are in the United States legally and22
those who are unauthorized. Nor is it possible to differentiate between different
categories of noncitizens (e.g., legal permanent residents, temporary workers,
students, refugees, asylees, etc.). In addition, it is unknown how many of the
Mexican noncitizens and naturalized U.S. citizens from Mexico in the sample would
still qualify for Social Security benefits without a totalization agreement.
The population characteristics analyzed in this paper were chosen because they
relate to aspects of the Social Security benefit formula (e.g., income and factors that
affect income) or eligibility (e.g., age, number of dependents). The comparisons
discussed in the text of this report are statistically significant at the 95% confidence23, 24


level, unless stated otherwise.
20A naturalized citizen is a legal immigrant who has become a U.S. citizen. To become a
naturalized citizen, aliens must live in United States continuously for five years as a legal
permanent resident (or three years in the case of spouses of a U.S. citizen), show that they
have good moral character, demonstrate the ability to read, write, speak, and understand
English, and pass an examination on U.S. government and history. CRS Report RS20916,
Immigration and Naturalization Fundamentals, by Ruth Ellen Wasem, p. 5.
21The reason that naturalized U.S. citizens from the totalization countries and Mexico are
compared separately from U.S. citizens is that, although under the Social Security Act they
are treated as U.S. citizens, it is possible that individuals in those groups have previously
worked in their country of birth and would have earned credits under both the U.S. Social
Security system and the system of their native country.
22Of the estimated 10.3 million unauthorized aliens residing in the United States, 57% are
from Mexico, while 23% are from other Latin American countries, 9% from Asia, and only
6% are from Canada and Europe, where the majority of the totalization countries are
located. Pew Hispanic Center, Estimates of the Size and Characteristics of the
Undocumented Population, by Jeffrey Passel, Mar. 21, 2005.
23See Appendix B for an explanation of confidence levels.
24One of the arguments for a totalization agreement with any country is the savings to
individuals and companies when the employer sends the individual to work in the other
country. Since the CPS does not have firm-level information, this report does not explore
how many U.S. companies send workers to branches in Mexico, or how many Mexican
companies send Mexican workers to their branches in the United States.

Table 1. Estimated Resident Population by Citizenship Status
and Gender, March 2004
(in 000s)
Citizen statusPopulationMaleFemale
U.S. Citizens263,33848.8%51.2%
Mexican noncitizens8,44756.3%43.7%
Naturalized U.S. citizens from Mexico2,00650.5%49.5%
Noncitizens from totalization countries a1,73145.7%54.3%
Naturalized U.S. citizens from totalization countries a1,82143.4%56.6%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Estimates for totalization countries do not include Luxembourg.
Population Characteristics
Population. The number of Mexican-born noncitizens and naturalized
citizens residing in the United States is much higher than the comparative
populations from totalization countries. Table 1 shows that the number of Mexican
nationals living in the United States is five times larger than the number of citizens
from all totalization countries combined. In addition, there are approximately
185,000 more naturalized U.S. citizens from Mexico living in the United States than
the number of naturalized U.S. citizens from all totalization countries combined.
Gender. Table 1 also shows that, more than any other group, Mexican
noncitizens are more likely to be male (56.3%). On the other hand, noncitizens and
naturalized citizens from the totalization countries are more likely to be female
(54.3% and 56.6%, respectively). A possible reason for the higher percentage of
females among naturalized citizens from totalization countries is that over a third
(37.6%) of the population is age 65 and over, and the proportion of females is greater
among those 65 and older for all population groups in the United States (see Figure

1 for the age distributions of the populations).



Figure 1. Distribution of Population by Citizenship Status
and Age, March 2004


Mexican NoncitizensTotalization Noncitizens
16-2412.5%16-2419.5%16-2410.6%25-3421.4%U.S. Citizens
Less than 1623.8%25-34
12.4%Less than 16Less than 16
11.2%25-3433.0% 8.9%
65+2.8% 35-44
35-4414.5% 65+ 55-64 22.7% 65+11.0%
12.4% 45-54 3.9% 55-64
45-5414.4% 55-6410.1% 35-44 9.1% 45-54 10.2%
20.6% 15.3%
Naturalized MexicansNaturalized Totalization
25-3417.9% 25-346.2%35-4411.6%45-5417.4%
35-4431.3%
16-245.4% 16-24
Less than 161.4%Less than 162.4%3.9%55-64
65+11.2% 20.9%
45-5421.7% 55-6411.1% 65+
37.6%
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Notes: Estimates for totalization countries do not include Luxembourg. Totals may not equal 100% due to rounding.
Age. As Figure 1 illustrates, Mexican noncitizens tend to be younger than
noncitizens from the totalization countries: only 15.8% are 45 or older, compared
to 36.5% of noncitizens from the totalization countries. Mexican noncitizens also
tend to be younger than U.S. citizens and naturalized U.S. citizens from Mexico and
the totalization countries. Naturalized citizens, both from Mexico and totalization
countries, tend to be older than their noncitizen counterparts. In general, noncitizens
must reside in the United States for five years as legal permanent residents before
applying for citizenship.
U.S. citizens, more than any of the other groups, are the more likely to be under
the age of 16: 23.8% of the U.S. population is under the age of 16, compared to

11.2% of Mexican noncitizens and 8.9% of noncitizens from totalization countries.


Very few of the naturalized U.S. citizens from Mexico (1.4%) or from the totalization25
countries (2.4%) are under the age of 16, due to the fact that aliens must have
continuously resided in the United States as legal permanent residents (LPRs) for five
years before naturalizing, and that children born in the United States to noncitizen
25The difference between the percent of noncitizens from totalization countries and from
Mexico who are under the age of 16 is not significant. Similarly, the difference between the
percent of the naturalized populations from totalization countries and those from Mexico
who are under the age of 16 is not significant.

parents are, by birth, U.S. citizens.26 However, 19.5% of Mexican noncitizens are
between the ages of 16 and 24, compared to 12.4% of U.S. citizens, 10.6% of
noncitizens from totalization countries, 5.4% of naturalized U.S. citizens from
Mexico, and 3.9% of naturalized citizens from totalization countries.
One-third ( 33.0%) of the Mexican noncitizens are between the ages of 25 and
34, and the majority of Mexican noncitizens are between the ages of 25 and 44
(56.3%). Comparatively, only 21.4% of noncitizens from totalization countries,
12.4% of U.S. citizens, 17.9% of naturalized Mexicans, and 6.2% of naturalized
citizens from totalization countries are between the ages of 25 and 34.27 In addition,
unlike Mexican noncitizens, no other group has a majority of their members between
the ages of 25 and 44. The closest is the naturalized Mexicans of whom 49.2% are
between the ages of 25 and 44. Conversely, the majority of naturalized U.S. citizens
from totalization countries are over the age of 54 (58.5%) while only 6.7% of
Mexican noncitizens are over the age of 54. The percentages of U.S. citizens,
naturalized U.S. citizens from Mexico, and noncitizens from totalization countries
over the age of 54 are similar (22.8%, 22.3%, and 21.2%, respectively).
Education. Figure 2 shows that, in general, noncitizens from totalization
countries are substantially better educated than the other comparison populations.
Mexican noncitizens and naturalized citizens from Mexico tend to have the lowest
levels of educational attainment. Figure 2 shows that 65.1% of the Mexican
noncitizens in the United States over the age of 18 have less than a high school
diploma, while only 3.2% have a Bachelor’s or advanced degree. By comparison,
11.2% of noncitizens from totalization countries have less than a high school
diploma, while 42.2% have a college or advanced degree. Similarly, 31.6% of
Mexican noncitizens have a high school degree or some college, while 46.6% of
noncitizens from totalization countries have a high school degree or some college.


26For more information on naturalization and automatic citizenship see, CRS Report
RS20916, Immigration and Naturalization Fundamentals, by Ruth Ellen Wasem.
27The comparison of naturalized U.S. citizens from Mexico and noncitizens from the
totalization countries is statistically significant at the 90% confidence level.

Figure 2. Distribution of Population Ages 18 and Over by Citizenship
Status and Educational Attainment, March 2004


U.S. 13.0%32.6%28.7%25.8%
Citizens
Mexican 65.1% 23.2% 8.4% 3.2%
Nonc itizens
T o ta liza t io n 11.2% 22.5% 24.1% 42.2%
Nonc itizens
Naturalized 51.6%26.4%13.2%8.8%
Mexicans
N a tu r a lize d 18.3% 30.8% 22.4% 28.5%
T o ta liza t io n
0% 20% 40% 60% 80% 100%
Less than a high school diploma High school graduate
Some college/Associate degreeBachelor's or advanced degree
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Notes: Estimates for totalization countries do not include Luxembourg. Totals may not add to 100% due to rounding.
Naturalized U.S. citizens from Mexico are much more likely than naturalized
U.S. citizens from totalization countries to have less than a high school diploma
(51.6% compared to 18.3%) and much less likely to have a Bachelor’s or advanced
degree (8.8% versus 28.5%). In addition, 39.6% of naturalized U.S. citizens from
Mexico have a high school degree or some college, compared to 53.2% of naturalized
U.S. citizens from totalization countries. Comparatively, for U.S. citizens 13.0%
have less than a high school diploma, 61.3% have a high school degree or some
college, and 25.8% have a college or advanced degree.28
Characteristics of Persons in the Labor Force
Labor Force Participation Rates. As shown in Figure 3, the labor force
participation rates of Mexican noncitizens (69.5%) is higher than that of noncitizens
from the totalization countries (61.6%), U.S. citizens (65.5%), and naturalized U.S.
citizens from the totalization countries (49.4%). In addition, the labor force
participation rates of noncitizens from totalization countries is lower than that of U.S.
citizens. The labor force participation rates of Mexican noncitizens and naturalized
U.S. citizens from Mexico are not statistically different (69.5% versus 68.2%). One
of the reasons for the differences in labor force participation rates may be due to
28The difference between the percentage of U.S. citizens with high school diplomas and
naturalized U.S. citizens from totalization countries with high school diplomas is not
significant.

differences in the age distributions of the different citizenship groups: 86.1% of
Mexican noncitizens and 87.4% of naturalized Mexicans are between the ages of 16
and 64, compared to 63.9% of U.S. citizens. One reason for the low labor
participation rate among naturalized citizens from the totalization countries is that
over a third of persons in this group are 65 or older, and, in general, labor force
participation is lower for older persons. (See Figure 1.)
Figure 3. Labor Force Participation Rate and Unemployment Rate by
Citizenship Status, March 2004


100.0% Percentage
U.S. Citizens
Mexican Noncitizens
80.0%Totalization Noncitizens
69.5%68.2%Naturalized Mexicans
65.5%Naturalized Totalization
61.6%
60.0%
49.4%
40.0%
20.0%
6.0% 8.2% 4.5% 5.0% 2.7%
0.0%
Labor Force Participation RateUnemployment Rate
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Estimates for totalization countries do not include Luxembourg.
Unemployment Rates. Figure 3 also shows that for persons 16 and over,
the unemployment rate is higher for Mexican noncitizens (8.2%) than for noncitizens
from totalization countries (4.5%) and U.S. citizens (6.0%), as well as for naturalized
U.S. citizens from Mexico (5%). Naturalized U.S. citizens from totalization
countries have the lowest unemployment rate (2.7%) of all the groups.29
Labor Force Participation by Age. Labor force participation rates vary by
age. One of the reasons for the higher overall labor force participation rate of
Mexican noncitizens is that participation rates are higher among the youngest (ages
16 to 24) and oldest groups of workers (age 65 and older). Figure 4 shows that, for
persons 65 and over, the labor force participation rate of Mexican noncitizens is
29The difference between the unemployment rates of noncitizens from totalization countries
and naturalized U.S. citizens from totalization countries is statistically significant at the 90%
confidence level.

higher than that of any other group. The labor force participation rate for persons
65 and older is twice as high for Mexican noncitizens as for noncitizens from
totalization countries (22.1% compared to 11.0%). In addition, the labor force
participation rate for Mexican noncitizens between the ages of 16 and 24 is much
higher than that of noncitizens from totalization countries (66.5% versus 37.3%).
Mexican noncitizens between the ages of 25 and 64 are less likely than U.S. citizens
to be in the labor force.
Figure 4. Labor Force Participation Rate by Age and Citizenship
Status, March 2004


Labor Force Participation Rates
100.0%U.S. Citizens
%Mexican Noncitizens
.7%84.1%2.2%%.9%%.3%.4%85.1.7%Totalization Noncitizens
838.2798.28180.8%.3%80Naturalized Mexicans
% 77 .6% 7 767680.0%
2.9722%%Naturalized Totalization
.5% 7 67. .9%.0
.2%66 6365 % .8%
.4% 63 6% .1% 59
59 55. 574.060.0%
5
.3%40.0%
3 7
%
2.1
.8% 2 0% 3.4%20.0%
14 11. .6% 1
9
0.0%
16-2425-3435-4445-5455-6465 and over
Age
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Estimates for totalization countries do not include Luxembourg.
Unemployment Rates by Age. The unemployment rate for noncitizens
from totalization countries is lower than that of noncitizens from Mexico for those
25 to 34 years old, and 45 to 54 years old (see Figure 5). In addition, Mexican
noncitizens between the ages of 25 to 64 have higher unemployment rates than U.S.
citizens of the same ages.30 Conversely, 16 to 24 year old Mexican noncitizens have
lower unemployment rates than their U.S. citizen counterparts.
30The difference between the unemployment rates of Mexican noncitizens ages 55 to 64 and
U.S. citizens ages 55 to 64 is statistically significant at the 90% confidence level.

Figure 5. Unemployment Rates by Age and Citizenship Status


100.0%Unemployment Rates
80.0%U.S. CitizensMexican Noncitizens
Totalization Noncitizens
Naturalized Mexicans
60.0%Naturalized Totalization
40.0%
%%
.5% % % % 1.2% % 1 4.8 4 %0.920.0%
12 .3% 2% % % %.1 8.2 .5 1 8.7.8% % .6% % .7% %.5 % % .6% .7% 9% 9.1 % %
6 5. 4.1 3.9 3.87 76 2.7 6 2.3 5 2.86 2.4 5 5 4..9% 3.4 2.7 .6%
1 10.0%
16-2425-3435-4445-5455-6465 and over
Age
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Notes: Estimates for totalization countries do not include Luxembourg. Following BLS practice,
estimates are not shown for Naturalized U.S. citizens from totalization countries between the ages of
25 and 34 because the estimated labor force is less than 75,000.
Gender of Persons in the Labor Force. For each citizenship group, men
account for the largest share of persons in the labor force. Among Mexican
noncitizens, 72.4% of persons in the labor force are men (see Figure 6). This
percentage compares to 53.1% for noncitizens from totalization countries. Among
naturalized citizens from Mexico, 59.8% of persons in the labor force are men,
compared to 53.6% of naturalized citizens from totalization countries. As is well
documented, women tend to earn 76-79 cents for every dollar earned by men, and,
on average, earn less than men over the life course.31 In addition, due to the structure
of the Social Security benefit formula, lower earners receive a higher replacement
rate on their contributions.
31For a full discussion of the gender wage gap see CRS Report 98-278, The Gender Wage
Gap and Pay Equity: Is Comparable Worth the Next Step?, by Linda Levine.

Figure 6. Gender by Citizenship Status for Those in the Labor Force


Ma l e F e ma l e
Percent
100%
27.6%
47.8% 46.9% 40.2% 46.4%80%
60%
72.4%40%
52.2% 53.1% 59.8% 53.6%
20%
0%
U.S. Mexican Totalization Naturalized Naturalized NoncitizensCitizens
M e x i cans To talizatio nN o ncitizens
Labor Force Participants
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Estimates for totalization countries do not include Luxembourg. Labor force participants include the
employed and unemployed.
Disabled Workers. Table 2 shows that noncitizens from Mexico and
noncitizens from totalization countries have similar proportions of the population
who are not in the labor force due to disability (2.1% and 1.6%, respectively). The
percentage (4.8%) of U.S. citizens who are not working because a disability is greater
than the percentage of noncitizens from both Mexico and the totalization countries,
and naturalized U.S. citizens from the totalization countries (2.8%). Naturalized U.S.
citizens from Mexico have the highest percentage (5.9%) of workers not in the labor
force due to disability.32 The lower percentage of Mexican noncitizens who are not
in the labor force because of disabilities may be due to several factors. Mexican
noncitizens tend to be younger (and, therefore, perhaps healthier) than workers from
other citizenship groups. Persons with disabilities may not come to the United States
to work. Persons who become disabled while in the United States may return to their33
native countries.
32The difference between the percentage of disabled U.S. citizens and disabled naturalized
U.S. citizens from Mexico is statistically significant at the 90% confidence level.
33As discussed above, fewer quarters of coverage are needed to receive Social Security
disability benefits than old-age and survivors benefits.

Table 2. Estimated Percent of Persons Not in the Labor Force
Because of a Reported Disability, by Citizenship Status,
March 2004
Not in the labor force because
Citizenship statusof a disability
U.S. Citizens4.8%
Mexican noncitizens2.1%
Naturalized U.S. citizens from Mexico5.9%
Noncitizens from totalization countries a1.6%
Naturalized U.S. citizens from totalization countries a2.8%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
Note: Estimates are for persons 16 and over and do not include retired persons.
a. Estimates for totalization countries do not include Luxembourg.
Earnings. Among the five citizenship groups, Mexican noncitizens tend to
have lower annual earnings than workers in the other citizenship groups. Figure 7
shows that the median annual earnings for noncitizens from totalization countries are
more than twice the median earnings for noncitizens from Mexico ($15,600
compared to $32,000). The median annual earnings of naturalized citizens from
totalization countries are $10,000 more than the median earnings of naturalized U.S.
citizens from Mexico ($32,000 compared to $22,000). The median earnings
($32,000) of citizens and noncitizens from the totalization countries are also higher
than the median earnings of U.S. citizens ($27,000).34
As illustrated in Figure 7, the majority (63.8%) of employed Mexican
noncitizens in the United States earned under $20,000 in 2003, and were more likely
than any other citizenship group to earn less than $20,000. Forty-three percent of
naturalized U.S. citizens from Mexico earned less than $20,000, compared to 36.4%
of U.S. citizens and 30.5% of noncitizens from totalization countries.
Conversely, noncitizens from the totalization countries had the highest
concentration of person earning $80,000 or more. While 15.2% of noncitizens from
totalization countries earned at least $80,000, only 8% of U.S. citizens, 1.5% of
naturalized U.S. citizens from Mexico, and 0.7% of Mexican noncitizens earned the35
same amount.


34The results shown in Figure 7 may be affected by rounding. When answering survey
questions about annual earnings, many respondents may round off the amount they earn.
35The difference between the percent of naturalized U.S. citizens and noncitizens from
totalization countries earning at least $80,000 is not statistically significant, but the
differences between the percent of naturalized U.S. citizens from the totalization countries
and the other groups earning at least $80,000 are statistically significant.

Figure 7. Distribution of Employed Persons and Median Earnings by Citizenship
Status and Annual Earnings, 2003


U.S. Citizens36.4%31.1%17%7.6%3.2%4.8%
Median Income: $27,000
Mexican 63.8%29.1%5.2%1.9%
NoncitizensMedian Income: $15,600
1.5%
Na t u ra lize d 43.2% 42.4% 9.2% 3.7%
MexicansMedian Income: $22,000
T o t a liza t io n 30.5% 27.3% 17.6% 9.5% 5.1%
Noncitizens10.1%Median Income: $32,000
Na t u ra lize d 24% 33.4% 20.4%
Totalization8.8%4.7%8.7%Median Income: $32,000
0% 20% 40% 60% 80% 100%
Under $20,000$20,000-$39,999$40,000-$59,999
$60,000-$79,000 $80,000-$99,000 $100,000+
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Estimates for totalization countries do not include Luxembourg. Totals may not add to 100% due to rounding.
As discussed above, under the Social Security benefit in 2005, Social Security-
covered workers and their employers each pay 6.2% of earnings up to $90,000 (this
amount is indexed to average wage growth). Thus, higher wage workers pay more
into the system than lower wage workers (unless both workers are earning over
$90,000). Nonetheless, the Social Security benefit formula is “tilted” so that lower
wage workers receive a higher replacement rate in Social Security benefits than
workers with higher lifetime earnings.
Occupations. Several factors may affect relative earnings, including work
experience, education, gender, industry and occupation, and hours worked. Figure
1 above showed that Mexican noncitizens tend to be younger and, therefore, have
less work experience than persons from other citizenship groups. Figure 3 showed
that the educational attainment of Mexican noncitizens tends to be lower than that for
persons in other citizenship groups.
Table 3 shows that the highest concentration of Mexican noncitizens (30.4%)
and naturalized U.S. citizens from Mexico (22.3%) work in service occupations,
many of which pay lower wages than other occupations. Comparatively, 10.4% of
noncitizens from totalization countries, 13.2% of naturalized U.S. citizens from
totalization countries, and 15.1% of U.S. citizen workers are in service occupations,
and there is no statistical difference between the concentration of service workers in
the three groups. Noncitizens from totalization countries (23.1%) are more likely
than noncitizens from Mexico (10.4%) to be in sales and office occupations, while
U.S. citizens (26.8%) are more likely than both groups to be in these occupations. By

contrast, noncitizens from totalization countries have the highest concentration of
workers in professional occupations (28.0%), while only 2.2% of Mexican
noncitizens and 9.3% of naturalized U.S. citizens from Mexico work in professional
occupations. A similar percentage of U.S. citizens (21.4%) and naturalized U.S.
citizens from totalization countries (22.3%) are in professional occupations.
Furthermore, a higher percentage of noncitizens from totalization countries,
U.S. workers, and naturalized U.S. citizen workers from totalization countries are in
management, business, and financial occupations than noncitizens and naturalized
U.S. citizens from Mexico: 21.3% of noncitizens from totalization countries and

21.2% naturalized U.S. citizens from totalization countries are in management,


business, and financial occupations compared to 15.4% of U.S. citizens, 5.9% of
naturalized U.S. citizens from Mexico, and 2.9% of noncitizens from Mexico.36
The second highest occupational concentration of Mexican noncitizen workers
occurs in construction and extraction occupations, with 21.3% of the workers in
those occupations. Among naturalized U.S. citizens from Mexico, 10.2% are in
construction occupations, while the percentage of U.S. citizen workers, noncitizens
from totalization countries, and naturalized U.S. citizen workers from totalization
countries is significantly less (5.0%, 6.1%, and 4.6%, respectively). Similarly, the
concentration of naturalized U.S. citizens from Mexico, and noncitizens from
Mexico in production occupations37 is more than two times higher than the
concentration of U.S. citizen workers, noncitizens from totalization countries, and
naturalized U.S. citizen workers from totalization countries in production
occupations.


36The difference in the percentage of persons in management, business, and financial
occupations for noncitizens from totalization countries and naturalized U.S. citizens from
totalization countries is not statistically significant.
37Production occupations include occupations such as machine operators, assemblers,
printers, wood workers, dressmakers, bakers, laundry workers, and meat processing workers.
U.S. Department of Labor, Bureau of Labor Statistics, Standard Occupational Classification
System, available at [http://www.bls.gov/soc/home.htm].

Table 3. Distribution of Employed Persons by Citizenship
Status and Occupation, March 2004
(persons ages 16 and over)
Occupation Percent Ranking
U.S. citizens
Management, business, and financial occupations15.4%3
Professional and related occupations21.4%2
Service occupations15.1%4
Sales and office occupations26.8%1
Farming, fishing, and forestry occupations0.5%9
Construction and extraction occupations5.0%7
Installation, maintenance, and repair occupations3.7%8
Production occupations6.3%5
Transportation and material moving occupations6.0%6
Total100.2%
Mexican noncitizens
Management, business, and financial occupations2.9%8
Professional and related occupations2.2%9
Service occupations30.4%1
Sales and office occupations10.4%4
Farming, fishing, and forestry occupations4.9%6
Construction and extraction occupations21.3%2
Installation, maintenance, and repair occupations4.1%7
Production occupations14.4%3
Transportation and material moving occupations9.5%5
Total100.0%
Naturalized U.S. citizens from Mexico
Management, business, and financial occupations 5.9%7
Professional and related occupations9.3%6
Service occupations22.3%1
Sales and office occupations17.5%3
Farming, fishing, and forestry occupations3.0%9
Construction and extraction occupations10.2%4
Installation, maintenance, and repair occupations4.1%8
Production occupations17.9%2
Transportation and material moving occupations9.8%5
Total100.0% a
Noncitizens from totalization countries
Management, business, and financial occupations21.3%3
Professional and related occupations28.0%1
Service occupations10.4%4
Sales and office occupations23.1%2
Farming, fishing, and forestry occupations0.0%9
Construction and extraction occupations6.1%5
Installation, maintenance, and repair occupations1.7%8
Production occupations6.1%5
Transportation and material moving occupations3.3%7
Total100.0% a
Naturalized U.S. citizens from totalization countries
Management, business, and financial occupations21.2%3
Professional and related occupations22.3%2
Service occupations13.2%4



Occupation Percent Ranking
Sales and office occupations27.4%1
Farming, fishing, and forestry occupations0.1%9
Construction and extraction occupations4.6%6
Installation, maintenance, and repair occupations2.2%8
Production occupations5.9%5
Transportation and material moving occupations3.1%7
Total100.0%
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Details may not add to totals because of rounding. For a definition of the occupational groups
see U.S. Department of Labor, Bureau of Labor Statistics, Standard Occupational Classification
System, available at [http://www.bls.gov/soc/home.htm].
a. Estimates for totalization countries do not include Luxembourg.
Full-Time/Part-Time Status. Figure 8 shows that, in March 2004, the
majority of employed persons for all citizenship groups usually work full-time.
Although Mexican noncitizens earn less than workers in the other citizenship groups,
they (as well as naturalized citizens from Mexico) are more likely than workers in
other groups to work full-time: 88.5% of Mexican noncitizens and 90.9% of
naturalized Mexican citizens work full-time. The percentages of noncitizens and
naturalized citizens from totalization countries who work full-time do not differ
significantly from each other (82.6% and 83.7%, respectively) or from the rate for
U.S. citizens (80.9% usually work full-time).
Figure 8. Distribution of Employed Persons by Citizenship
Status and Full-Time and Part-Time Employment,
March 2004


100.0% Percent
9.1%17.4%
19.1% 11.5% 16.3%
80.0%
60.0%
P a rt -t ime
Fu ll-time
40.0% 80.9% 88.5% 90.9% 82.6% 83.7%
20.0%
0.0%
U.S. CitizensMexican Totalization Naturalized Naturalized
Noncitizens Noncitizens Mexicans T o t a liza t io n
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Note: Estimates for totalization countries do not include Luxembourg.

Arrival Year. In general, naturalized U.S. citizens from Mexico and the
totalization countries have been in the United States longer than their noncitizen
counterparts (see Figure 9). Nonetheless, naturalized U.S. citizens from totalization
countries were more likely to arrive prior to 1986 than naturalized U.S. citizens from
Mexico (83.6% compared to 71.4%). In addition, naturalized U.S. citizens from
Mexico (6.0%) were more than three times as likely to have arrived after 1995 than
naturalized U.S. citizens from totalization countries (1.9%), although the percentages
are small in both cases. Similarly, noncitizens from totalization countries were more
likely than noncitizens from Mexico to have arrived prior to 1975 (16.1% versus
5.8%); and they were slightly less likely than Mexican noncitizens to have arrived
after 1995 (37.6% compared to 43.5%). Research has shown that the earning of
noncitizens are correlated to the length of time an alien is in the United States, with
those who have been in the United States longer having higher earnings.38
Figure 9. Arrival Year for Those in the Labor Force Over Age 16 for
Naturalized U.S. Citizens and Noncitizens from Mexico
and Totalization Countries


1975-198517.6%Before 197529.4%
1986-199533.2%
Before 19755.8%
1975-198542.0% 1996-2004
6.0%
1996-200443.5%1986-199522.6%Mexican NoncitizensNaturalized Mexicans
1975-198518.9%Before 197553.7%
Before 197516.1%
1986-199527.5%
1996-20041.9%
1986-199514.5%
1996-200437.6%1975-198529.9%Totalization Noncitizens
Naturalized Totalization
Source: Calculated by CRS from the March 2004 Current Population Survey (CPS).
Notes: Estimates for totalization countries do not include Luxembourg. Totals may not equal 100% due to
rounding.
Dependents. Mexican noncitizens in the labor force have a higher average
number of dependents residing in the United States (1.7) than noncitizens from
totalization countries (1.4). U.S. citizens and naturalized U.S. citizens from
totalization countries have an average of 1.2 and 1.3 dependents, respectively.
Naturalized U.S. citizens from Mexico average 2.0 dependents, which is the highest
38For example, see T. Paul Schultz, “Immigrant Quality and Assimilation: A Review of the
U.S. Literature,” Journal of Population Economics, vol. 11 (1998), pp. 239-252.

average number of dependents for any of the citizenship groups. Among persons in
the labor force who have at least one dependent (i.e., excluding persons living alone
or with unrelated persons), Mexican noncitizens average 2.4 dependents, which is
similar to the average number of dependents for naturalized U.S. citizens from
Mexico (2.3), and higher than the average number of dependents for noncitizens and
naturalized U.S. citizens from totalization countries (1.9 and 1.6), and U.S. citizens
(1.8).
Table 4. Estimated Number of Dependents Residing in the
United States Per Worker, by Citizenship Status,
March 2004
Number of
dependents per
worker, excluding
Number ofindividuals living
dependents peralone or with
worker, allaunrelateda
f amilies i ndi vi dual s
Citizen status(1)(2)
U.S. citizens1.21.8
Mexican noncitizens1.72.4
Noncitizens from totalization countriesb1.41.9
Naturalized U.S. citizens from Mexico2.02.3
Naturalized U.S. citizens from totalizationb1.31.6
countries
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Families consist of persons living together and related by birth, marriage, or adoption and, in
column 1, include persons living alone or with unrelated individuals. In column 2, families are
groups of two or more related persons. A household may include more than one family.
Dependents include spouses, children under 18, full-time high school students under the age of
19, and persons over 18 with disabilities.
b. Estimates for totalization countries do not include Luxembourg.
The average number of dependents for noncitizens from Mexico and the
totalization countries may be higher than the figures shown in Table 4. As shown
above, 72.4% of Mexican noncitizens in the labor force are male (compared to 53.1%
of noncitizens from the totalization countries). Among these men, 8.0% report that
they are married but that their spouse is not living in their U.S. household. The
spouse may be elsewhere in the United States or in Mexico (or in another country).
Only 1.3% of noncitizen men from the current totalization countries report that they
are married but that their spouse is absent. Children may be living with the absent
spouse. Thus, the average number of dependents may be higher than shown above
for noncitizens from Mexico and the totalization countries, as dependents not
residing in the United States are not captured in the CPS. As discussed above, under
the Social Security Act, noncitizens who have not resided in the same relationship
with the worker in the United States for five years are not eligible for dependents or
survivors benefits while residing outside the United States. But the five-year



requirement is waived for citizens from countries with totalization agreements,
allowing dependent and survivor benefits to be paid to persons who have never lived
in the United States.
Conclusion
In addition to being much larger than the population of persons from the
totalization countries in the United States, the Mexican population — both
noncitizens and naturalized citizens — in the United States has a different socio-
economic profile than U.S. citizens and persons in the United States from totalization
countries. Individuals from totalization countries tend to have more education and
higher earnings than persons from Mexico and the United States. The population
from Mexico tends to be younger and more heavily male. A smaller proportion of
the Mexican noncitizen population is not in the labor force because of disability and
their labor force participation rates are higher. Mexican persons in the U.S. labor
force tend to have more dependents in their U.S. households. Because Mexican
workers may have lower lifetime earnings, they may receive a higher replacement
rate in Social Security benefits than workers with higher lifetime earnings. The fact
that Mexican noncitizens tend to spend more years in the labor force does not mean
that they contribute more to the Social Security system than noncitizens from
totalization countries who have, on average, higher incomes.



Appendix A: Variation Among the Totalization
Countries
Brief Overview of Methodology
The current totalization countries are not a homogenous group. This section of
the report explores socio-economic variations among the totalization countries. The
data used are from the March CPS (see Appendix B). The sample size for
noncitizens and naturalized U.S. citizens from totalization countries is not large
enough to perform separate analyses for each country.39 Thus, analyses are presented
for noncitizens from Canada, Chile, Italy, Germany, and South Korea, and for
naturalized U.S. citizens from Canada, Ireland, Italy, Germany, Greece, Portugal, and
South Korea. Tests of statistical significance were performed for each of the
separately analyzed totalization country populations compared to the corresponding
population from Mexico. Unless noted otherwise, the findings discussed in this
appendix are significant at the 95% confidence level.
Analysis
Population. As discussed earlier in this report (see Table 1) and illustrated
in Table A1, the number of Mexican noncitizens in the United States is much higher
than the number of noncitizens from all totalization countries combined. In addition,
the number of naturalized citizens from totalization countries is less than the number
of naturalized U.S. citizens from Mexico. Accordingly, the population in the United
States from Mexico is much larger than that from any individual totalization country.
Age. As shown in Table A2, although there are differences between the age
distributions of naturalized U.S. citizens from different totalization countries, none
of the countries has an age distribution similar to that of naturalized U.S. citizens
from Mexico. With the exception of South Korea, the naturalized populations from
totalization countries tends to be older than the population of naturalized Mexicans.
The population of naturalized U.S. citizens from South Korea is more heavily
concentrated at the lower end of the age distribution (i.e., below 35 years old) than
the naturalized population from Mexico.
Similarly, there are differences between the age distributions of noncitizens
from totalization countries, but none of the countries has an age distribution
equivalent to that of Mexican noncitizens. As with the naturalized populations, in
general, noncitizens from totalization countries tend to be older than noncitizens
from Mexico. Nonetheless, the age distribution of Chilean noncitizens is statistically
equivalent to that of Mexican noncitizens except for those between the ages of 25 and

34 (a higher concentration of Mexican noncitizens) and those 55 to 64 (a higher40


concentration of Chilean noncitizens).
39Unless the estimated population from a country was at least 75,000 persons the country
was not included in the analysis.
40The difference between the percent of Chilean noncitizens and Mexican noncitizens
(continued...)

Table A1. Estimated Population by Citizenship Status: United
States, Mexico, and Totalization Countries, March 2004
P o pula t io n
Citizenship status(in 1,000s)
Naturalized
Canada 257
Germany 285
Greece 109
Ireland 120
Italy 327
P o r t uga l 8 4
South Korea378
Mexico 2,006
No ncit izens
Ca na d a 410
Chile 76
Germany 239
Italy 127
South Korea385
Mexico 8,447
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
Table A2. Distribution of Population by Citizenship Status and
Age for Select Totalization Countries, March 2004
Less than
Citizenship status1616-2425-3435-4445-5455 -6465 +
Naturalized
Ca na d a 1.5% 5.0% 9.3% 7.7% 18.8% 14.8% 43.0%
Germany 1.5% 0.8% 1.5% 7.4% 11.8% 31.3% 45.7%
Greece 0.0% 1.3% 1.6% 12.1% 13.7% 21.4% 49.9%
Ireland 0.0% 0.0% 5.4% 12.4% 14.0% 22.0% 46.3%
Italy 0.0% 1.1% 3.9% 7.7% 13.8% 23.7% 49.8%
Portugal 0 .4% 2 .2% 16.9% 19.0% 25.4% 13.7% 22.5%
South Korea8.9%11.7%10.7%19.4%24.1%15.0%10.2%
All totalizationa2.4%3.9%6.2%11.6%17.4%20.9%37.6%
Mexico 1.4% 5.4% 17.9% 31.3% 21.7% 11.1% 11.2%
No ncit izens
Ca na d a 11.3% 13.1% 19.4% 19.8% 19.0% 10.5% 6.8%
Chile 11.3% 24.4% 15.4% 18.7% 8.0% 14.2% 8.0%
Germany 5.8% 8.2% 17.5% 23.0% 17.3% 10.4% 17.9%
Italy 13.3% 8.9% 12.8% 19.5% 8.3% 11.6% 25.6%
South Korea11.3%11.3%26.0%21.6%15.2%6.0%8.6%
All totalizationa8.9%10.6%21.4%22.7%15.3%10.2%11.0%
Mexico 11.2% 19.5% 33.0% 20.6% 9.1% 3.9% 2.8%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).


40(...continued)
between the ages of 55 and 64 is statistically significant at the 90% confidence level.

a. Estimates for totalization countries do not include Luxembourg.
Education. As shown in Table A3, there are major differences in educational
attainment among naturalized U.S. citizens from the different totalization countries.
The educational attainment of naturalized U.S. citizens from Italy, Portugal, and
Greece is more similar to the educational attainment of naturalized U.S. citizens from
Mexico than it is to the educational attainment of naturalized U.S. citizens from all
totalization countries combined. There is no statistical difference in educational
attainment between naturalized U.S. citizens from Mexico and from Greece. Seventy-
eight percent of naturalized citizens from Mexico have no schooling past high school,
compared to 75.9% of naturalized citizens from Portugal and 68.6% of naturalized
citizens from Italy. In general, 49.1% of naturalized citizens from totalization
countries did not pursue post-secondary education. Nonetheless, with the exception
of Greece, naturalized citizens from Mexico tend to be less educated than naturalized
citizens from any of the separately analyzed totalization countries.
Table A3. Distribution of Population Ages 18 and Over by
Citizenship Status and Educational Attainment for Select
Totalization Countries, March 2004
Co lleg e
Some college/graduate/
Less than highHigh schoolAssociateadvanced
Citizenship statusschoolgraduatedegreedegree
Naturalized
Ca na d a 10.7% 20.9% 30.9% 37.5%
Germany 13.1% 36.4% 27.6% 22.9%
Greece 46.1% 26.8% 12.4% 14.6%
Ireland 17.9% 41.7% 14.3% 26.1%
Italy 30.6% 38.0% 13.3% 18.2%
Portugal 31.5% 44.4% 15.7% 8.5%
South Korea8.9%25.4%22.6%43.1%
All totalizationa18.3%30.8%22.4%28.5%
Mexico 51.6% 26.4% 13.2% 8.8%
No ncit izens
Ca na d a 9.2% 20.0% 29.2% 41.5%
Chile 6.3%29.0%37.5%27.3%
Germany 6.6%30.6%28.3%34.5%
Italy 36.7% 31.6% 13.7% 18.0%
South Korea9.6%20.6%19.7%50.1%
All totalizationa11.2%22.5%24.1%42.2%
Mexico 65.1% 23.2% 8.4% 3.2%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Estimates for totalization countries do not include Luxembourg.
Mexican noncitizens have lower educational attainment than noncitizens from
each of the separately analyzed totalization countries. Noncitizens from each of the
separately analyzed totalization countries have significantly higher rates of post-



secondary education.41 Of the separately analyzed totalization countries, noncitizens
from Italy are the least educated, with only 31.7% having more than a high school
diploma, but significantly more Italian noncitizens have a college degree than those
from Mexico. As illustrated in Table A3, 11.6% of Mexican noncitizens have more
than a high school degree.
Labor Force Participation. Table A4 shows that, with the exception of
South Korea (65.4%), none of the naturalized U.S. citizens from any of the separately
analyzed totalization countries have labor force participation rates as high as
naturalized citizens from Mexico (68.2%). Only noncitizens from Italy and South
Korea (48.9% and 50.6%, respectively) have labor force participation rates
statistically different from the rate for noncitizens from Mexico (69.5%).
Table A4. Labor Force Participation Rate and Unemployment
Rate by Citizenship Status for Select Totalization Countries,
March 2004
(persons ages 16 and over)
Citizenship statusLabor force participation rateUnemployment rate
Naturalized
Canada 48.7% 3.6%
Germany 42.6% 2.1%
Greece 42.5% 3.0%
Ireland 39.2% 4.5%
Italy38.6% 4.1%
Portugal 54.1% 4.8%
South Korea65.4%2.6%a
All totalization49.4%2.7%
Mexico 68.2% 5.0%
No ncit izens
Canada 66.8% 3.5%
Chile 65.5% 3.5%
Germany 63.3% 3.4%
Italy 48.9% 6.8%
South Korea50.6%4.9%a
All totalization61.6%4.5%
Mexico 69.5% 8.2%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
Note: The labor force participation rate is the number of persons in the labor force divided by the size
of the corresponding population.
a. Estimates for totalization countries do not include Luxembourg.
The unemployment rates of naturalized citizens from totalization countries
analyzed separately are not significantly different from the unemployment rate for


41The difference between Italian noncitizens and Mexican noncitizens with some college is
not statistically significant; however, the difference between Italian noncitizens and
Mexican noncitizens with a B.A. or more education is significant at the 95% confidence
level.

naturalized U.S. citizens from Mexico. Only German and Canadian noncitizens have
statistically significant lower unemployment rates than Mexican noncitizens.42
Full-Time/Part-Time. Table A5 shows that a higher percentage of
naturalized U.S. citizen workers from Mexico work full-time than those from
Germany, Greece, and Italy.43 A higher percentage of Mexican noncitizens work full-44
time than noncitizens from Canada, Chile, and Germany.
Table A5. Distribution of Employed Persons by Citizenship
Status and Full-Time and Part-Time Employment for Select
Totalization Countries, March 2004
(persons ages 16 and over)
Citizenship statusFull-timePart-time
Naturalized
Canada 85.4% 14.6%
Germany 78.9% 21.1%
Greece 77.6% 22.5%
Ireland 87.0% 13.0%
Italy 81.6% 18.4%
Portugal 90.8% 9.2%
South Korea87.6%12.4%
All totalizationa83.7%16.3%
Mexico 90.9% 9.1%
No ncit izens
Canada 79.6% 20.5%
Chile 67.1% 33.0%
Germany 80.5% 19.5%
Italy 79.0% 21.0%
South Korea85.2%14.8%
All totalizationa82.6%17.4%
Mexico 88.5% 11.5%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
Note: Estimates are based on whether a person usually works full-time or part-time.
a. Estimates for totalization countries do not include Luxembourg.
Arrival. Although naturalized Mexicans in the labor force arrived more
recently than those from totalization countries, naturalized citizens from South Korea
have been as likely as naturalized U.S. citizens from Mexico to have arrived after


42The difference in unemployment rates for German and Mexican noncitizens is significant
at the 90% confidence level.
43The difference between Greece and Mexico in the percentage of naturalized citizens
employed full-time is significant at the 90% confidence level.
44The difference between Germany and Mexico in the percentage of noncitizens employed
full-time is significant at the 90% confidence level.

1985 (see Table A6):45 Nonetheless, while 6.0% of naturalized Mexicans arrived in

1996 or later, only 3.0% of naturalized South Koreans arrived during that period.


Chilean noncitizens tend to have arrived more recently than noncitizen
Mexicans: 61.2% of Chilean noncitizens arrived after 1995 compared to 43.5% of
Mexican noncitizens. The difference between the percentages of South Korean and
Mexican noncitizens who have arrived since 1996 is not significant.
Table A6. Arrival Year by Citizenship Status for Those in the
Labor Force for Select Totalization Countries
Arrival year
Citizenship statusBefore 19751976-19851986-19951996-2004
Naturalized
Ca na d a 57.7% 24.3% 16.4% 1.6%
Germany 80.9% 14.2% 4.3% 0.6%
Greece 62.9% 32.0% 5.1% 0.0%
Ireland 64.6% 19.3% 9.8% 6.3%
Italy 78.6% 15.5% 4.1% 1.8%
Portugal 49.7% 32.9% 16.5% 0.9%
South Korea16.9%55.0%25.1%3.0%
All totalizationa53.7%29.9%14.5%1.9%
Mexico 29.4% 42.0% 22.6% 6.0%
No ncit izens
Ca na d a 27.3% 11.3% 26.7% 34.8%
Chile 2.2%22.2%14.4%61.2%
Germany 15.3%25.7%21.2%37.8%
Italy 30.2% 8.7% 22.4% 38.7%
South Korea1.9%27.4%33.6%37.1%
All totalizationa16.1%18.9%27.5%37.6%
Mexico 5.8% 17.6% 33.2% 43.5%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Estimates for totalization countries do not include Luxembourg.
Gender. Table A7 shows that the population of naturalized citizens from
Mexico is evenly split between men and women (50.5% and 49.5%, respectively),
and is very similar to the gender distribution of naturalized U.S. citizens from Italy.
A majority of Mexican noncitizens is male (56.3%). The gender distribution of
noncitizens from Chile (65.2%) and Italy (50.8%) is similar to that of noncitizens
from Mexico.
Among noncitizens, 72.4% of Mexicans in the labor force are male, compared
to 53.1% of noncitizens from totalization countries. The gender distribution of
noncitizens from Chile and Italy in the labor force (72.% and 61.4% male,
respectively) is similar to that of Mexico.


45The difference between the percent of naturalized U.S. citizens from South Korea and
Mexico who arrived after 1995 is statistically significant at the 90% confidence level.

Table A7. Gender by Citizenship Status for Total Population
and Those in the Labor Force for Select Totalization Countries,
March 2004
Male Fema le Male Fema le
(total(total(in labor(in labor
Citizenship statuspopulation)population)force)force)
Naturalized
Ca na d a 47.4% 52.6% 53.6% 46.4%
Germany 35.1% 64.9% 51.7% 48.3%
Greece 40.5% 59.5% 62.6% 37.4%
Ireland 45.9% 54.1% 67.7% 32.3%
Italy 50.8% 49.2% 70.6% 29.4%
Portugal 38.4% 61.6% 42.5% 57.5%
South Korea42.2%57.8%45.7%54.3%
All totalizationa43.4%56.6%53.6%46.4%
Mexico 50.5% 49.5% 59.8% 40.2%
No ncit izens
Ca na d a 40.2% 59.8% 44.3% 55.7%
Chile 65.2%34.8%72.0%28.0%
Germany 31.5%68.5%33.0%67.0%
Italy 50.8% 49.2% 61.4% 38.6%
South Korea45.3%54.7%55.9%44.1%
All totalizationa45.7%54.3%53.1%46.9%
Mexico 56.3% 43.7% 72.4% 27.6%
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Estimates for totalization countries do not include Luxembourg.
Earnings. Naturalized citizens from Mexico as well as Mexican noncitizens
have lower annual earnings than workers from the totalization countries (see Table
A8). Among noncitizens, Mexican workers are more likely than workers from the
totalization countries to earn less than $20,000 annually and, except for workers from
Chile, less likely to earn $100,000 or more annually.



Table A8. Distribution of Employed Persons by Citizenship
Status and Annual Earnings for Select Totalization
Countries, 2003
(persons ages 16 and over)
Under $20,000- $40,000- $60,000- $80,000- $100,000
Citizenship status$20,000$39,999$59,999$79,999 $99,999or moreMedian
Naturalized
Ca na d a 20.7% 26.1% 34.4% 10.8% 2.5% 5.4% $40,000
Germany 36.5% 32.3% 12.7% 6.2% 6.5% 5.8% $24,000
Greece 30.9% 40.1% 15.5% 7.9% 0.0% 2.6% $30,000
Ireland 4.6% 35.7% 24.1% 9.9% 11.9% 13.9% $40,000
Italy 22.8% 20.9% 28.2% 10.3% 7.7% 10.1% $42,000
Portugal 28.5% 47.8% 14.6% 4.0% 1.4% 3.7% $28,000
South Korea21.4%35.1%14.8%12.0%5.2%11.5%$34,680
All totalizationa24.0%33.4%20.4%8.8%4.7%8.7%$32,000
Mexico 43.2% 42.4% 9.2% 3.7% 0.5% 1.0% $22,000
No ncit izens
Ca na d a 32.9% 18.4% 21.1% 11.7% 5.7% 10.4% $37,000
Chile 36.5% 40.3% 6.8% 14.9% 1.6% 0.0% $24,000
Germany 34.3% 27.5% 13.1% 10.0% 3.5% 11.7% $28,000
Italy 37.1% 21.5% 12.5% 6.3% 4.5% 18.2% $26,000
South Korea32.3%34.0%22.1%3.4%1.8%6.3%$30,000
All totalizationa30.5%27.3%17.6%9.5%5.1%10.1%$32,000
Mexico 63.8% 29.1% 5.2% 1.2% 0.4% 0.3% $15,600
Source: Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
a. Estimates for totalization countries do not include Luxembourg.
Occupations. As illustrated in Table A9, the occupational distributions for
naturalized workers from some totalization countries are similar to the occupational
distribution of naturalized workers from Mexico. Naturalized U.S. citizens from
Mexico, Greece, and Italy are similarly concentrated in service occupations, while
naturalized citizens from each of the separately analyzed totalization countries are at
least two times as likely to be in management, business, and financial occupational
group than naturalized U.S. citizens from Mexico.46 Furthermore, naturalized U.S.
citizens from Canada, Italy, and South Korea are more likely to be in professional
occupations than those from Mexico, while naturalized U.S. citizens from Greece,
Ireland, and Portugal are not significantly less likely to be in professional occupations
than those from Mexico. With the exception of naturalized citizens from Portugal
and Greece, naturalized U.S. citizens from each of the separately analyzed
totalization countries are less likely to be in production occupations than those from
Mexico.


46The difference between the percent of naturalized U.S. citizens from Greece and Mexico
in management occupations is statistically significant at the 90% confidence level. The
difference between the percent of naturalized U.S. citizens from Portugal and Mexico in
management occupations is not statistically significant.

The occupational distributions of noncitizens from each of the totalization
countries are more similar to each other than to the occupational distribution of
Mexican noncitizens (see Table A10). With the exception of Chile, noncitizens from
each of the totalization countries are more than five times as likely as noncitizens47
from Mexico to be in management and professional occupations. In addition,
noncitizens from each of the totalization countries are less likely to be in service and
transportation occupations than Mexican noncitizens. Chilean noncitizens are as
likely to be in construction occupations as Mexican noncitizens. Moreover, the
percent of Italian noncitizens in construction occupations is similar to that of
Mexicans in construction occupations. Finally, the concentration of South Korean
noncitizens in production occupations is similar to that of Mexican noncitizens.


47The difference between the percent of noncitizens from Chile and noncitizens from
Mexico in management occupations is statistically significant at the 90% confidence level.
The difference between the percent of noncitizens from Chile and noncitizens from Mexico
in professional occupations is not statistically significant.

CRS-32

9. Distribution of Naturalized Employed Persons by Occupation by Country for Select Totalization Countries,


March 2004
(persons ages 16 and over)
Naturalized CanadaNaturalized GermanyNaturalized GreeceNaturalized IrelandNaturalized Italy
O ccupa t io n Percent Rank P ercent Rank P ercent Rank P ercent Rank P ercent Rank
agement, business, and financial occupations21.1%225.3%218.4%326.0%217.4%4
essional and related occupations40.4%114.1%36.8%59.2%420.5%2
ice occupations8.7%412.8%436.1%18.7%522.5%1
es and office occupations16.6%333.1%121.0%231.4%117.9%3
ing, fishing, and forestry occupations0.0%90.0%90.0%80.3%80.0%9
struction and extraction occupations4.5%64.4%63.1%715.1%39.8%5
allation, maintenance, and repair occupations2.2%72.0%80.0%85.7%63.2%8
ction occupations0.5%85.8%511.5%43.7%74.5%6
iki/CRS-RL33015sportation and material moving occupations6.2%52.6%73.2%60.0%94.2%7
g/w
s.orNaturalized SouthNaturalized all
leakNaturalized PortugalKoreatotalizationaNaturalized Mexico
O ccupa t io n Percent Rank P ercent Rank P ercent Rank P ercent Rank
://wikiagement, business, and financial occupations15.0%317.2%321.2%35.9%7
httpessional and related occupations4.5%527.0%222.3%29.3%6
ice occupations4.4%611.0%413.2%422.3%1
es and office occupations37.4%132.4%127.4%117.5%3
ing, fishing, and forestry occupations2.4%80.0%80.1%93.0%9
struction and extraction occupations7.5%40.0%84.6%610.2%4
n, maintenance, and repair occupations0.9%92.9%62.2%84.1%8
ction occupations24.9%28.0%55.9%517.9%2
sportation and material moving occupations3.1%71.5%73.1%79.8%5
Calculated by CRS from the March 2004 Current Population Survey (CPS).
ates for totalization countries do not include Luxembourg.



CRS-33
Table A10. Distribution of Noncitizens Employed Persons by Occupation by Country for Select Totalization
Countries, March 2004
(persons ages 16 and over)
Noncitizens CanadaNoncitizens ChileNoncitizens GermanyNoncitizens Italy
O ccupa t io n Percent Rank P ercent Rank P ercent Rank P ercent Rank
agement, business, and financial occupations 19.9%217.0%320.4%327.2%2
essional and related occupations 36.3%112.3%523.3%215.4%4
ice occupations 14.4%412.6%415.4%45.5%6
es and office occupations15.3%325.5%133.0%127.6%1
ing, fishing, and forestry occupations0.0%90.0%80.0%80.0%7
struction and extraction occupations 4.9%621.1%20.0%818.6%3
n, maintenance, and repair occupations0.9%89.1%62.5%60.0%7
ction occupations 3.4%72.4%71.4%75.8%5
iki/CRS-RL33015sportation and material moving occupations4.9%50.0%84.0%50.0%7
g/w
s.orNoncitizens SouthNoncitizens all
leakKoreatotalizationaNoncitizens Mexico
O ccupa t io n Percent Rank P ercent Rank P ercent Rank
://wikiagement, business, and financial occupations 25.3%121.3%32.9%8
httpessional and related occupations 20.4%228.0%12.2%9
ice occupations 11.9%510.4%430.4%1
es and office occupations20.0%323.1%210.4%4
ing, fishing, and forestry occupations0.0%80.0%94.9%6
struction and extraction occupations 1.1%76.1%521.3%2
n, maintenance, and repair occupations0.0%81.7%84.1%7
ction occupations 17.8%46.1%514.4%3
sportation and material moving occupations3.5%63.3%79.5%5
Calculated by CRS from the Mar. 2004 Current Population Survey (CPS).
ates for totalization countries do not include Luxembourg.



Appendix B: Data and Detailed Methodology
The analysis in this report is based on data from the March 2004 Current
Population Survey (CPS). The Current Population Survey (CPS) is a household
survey conducted by the U.S. Bureau of the Census for the Bureau of Labor Statistics
(BLS) of the U.S. Department of Labor. The monthly CPS is the main source of
labor force data for the nation, including estimates of the monthly unemployment
rate. The CPS collects a wide range of demographic, social, and labor market
information. Currently, approximately 57,000 households are interviewed each
month. The monthly CPS sample is representative of the civilian noninstitutional
population; it does not include persons on active military duty.48 Each March, the49
CPS asks additional questions about earnings for the previous year.
The BLS defines the labor force as the sum of employed and unemployed
persons. Unemployed persons are individuals who are not working but who are
available and looking for work. Employed persons are individuals who are working
for a private or public employer, are self-employed, or who work 15 hours or more
a week as unpaid workers on a family farm or business. Also counted as employed
are persons who are temporarily absent from work because of illness, bad weather,
vacation, job training, labor-management disputes, childcare problems, maternity or
paternity leave, or other family or personal reasons.50
Citizenship Variable
The CPS uses five categories to define citizenship: (1) born in the United
States; (2) born in Puerto Rico or another outlying area of the United States; (3) born
abroad of U.S. citizen parents; (4) naturalized citizens; and (5) noncitizens. For the
analysis in this report, the first three categories were combined and defined as
“citizens.” The group of U.S. citizens excludes naturalized citizens from Mexico and
the current totalization countries. Naturalized U.S. citizens from Mexico and the
totalization countries were analyzed separately because it more likely that individuals
in those groups would have credits to combine under a totalization agreement (i.e.,
compared to naturalized U.S. citizens from other countries and natural-born U.S.
citizens).
Information on place of birth is collected for every household member in the
CPS sample, and for the parents of every household member. Individuals born in the
United States or its outlying areas, or whose parents were born in the United States


48U.S. Department of Commerce, Bureau of the Census, Measuring 50 Years of Economic
Change, Current Population Reports, P60-203, Washington, Sept. 1998, p. D-1. U.S.
Department of Labor, Bureau of Labor Statistics, Basic Monthly Survey, available at
[www.bls.census.gov/ cps/bglosary.htm] .
49U.S. Department of Commerce, Bureau of the Census, Current Population Survey: 2004
Annual Social and Economic (AASEC) Supplement, p. 1-1. Available at
[http://www.bls.census.gov/ cps/asec/sme thdoc.htm] .
50U.S. Department of Labor, Bureau of Labor Statistics, Current Population Survey: Design
and Methodology, Technical Paper 63, Mar. 2000, pp. 5-3 through 5-5.

or its outlying areas, are not asked questions about citizenship. Individuals born
outside the United States or its outlying areas, and whose parents were born outside
the United States or its outlying areas, are asked, “Are you a citizen of the United
States?” Respondents who answer “Yes” are coded as naturalized citizens, while
respondents who answer “No” are categorized as noncitizens. In the CPS,
individuals for whom no birthplace is provided are assigned a citizenship status
during the editing process. For example, the citizenship status of a child may be
assigned based on the citizenship status of the child’s mother.51 The CPS does not
attempt to verify the accuracy of responses to the questions about citizenship.
It is not possible using CPS data to differentiate between different categories of
noncitizens (e.g., legal permanent residents, temporary workers, students, refugees,
and asylees). Nor is it possible to differentiate between aliens who are in the United
States legally and those who are unauthorized. Thus, some of the respondents in the
noncitizens category who have never had authorization to work in the United States
would be ineligible for Social Security benefits, barring future changes to
immigration or Social Security policy.
Confidence Levels
The comparisons discussed in this report are statistically significant at the 95%
confidence level, unless stated otherwise. Estimates based on survey responses from
a sample of households have two kinds of error: nonsampling error and sampling
error. Examples of nonsampling error include information that is misreported and
errors made in processing collected information. Sampling error occurs because a
sample, and not the entire population, of households is surveyed. The difference
between an estimate based on a sample of households and the actual population value
is known as sampling error.52 When using sample data, researchers typically
construct confidence intervals around population estimates. Confidence intervals
provide information about the accuracy of estimated values. With a 95% confidence
interval and repeated samples from a population, 95% of intervals will generally
include the actual value of a population characteristic. For this report, confidence
intervals were calculated using a methodology suggested by the Census Bureau.


51[ h t t p : / / www.census.go v/ popul at i on/ www/ cps/ cpsdef .ht ml ] .
52U.S. Department of Labor, Bureau of Labor Statistics, Employment and Earnings, vol. 49,
Nov. 2002, pp. 147-148.