Methodology - American Immigration Council

National and State Data

The estimates that appear on the national and state pages were calculated by the American Immigration Council (the Council) research team using various publicly available datasets. Primary among these are microdata from the American Community Survey (ACS), downloaded from the Integrated Public Use Microdata Series (IPUMS) database. As of October 2, 2024, the data reflects analysis of the 2022 ACS microdata for national and state pages.

Except where otherwise noted (e.g., “undocumented immigrant” or “DACA-eligible”), we define an immigrant as anyone born outside the country to non-U.S. citizen parents who is a resident of the United States. This includes naturalized citizens, green card holders, temporary visa holders, refugees, asylees, and undocumented immigrants, among others.

Metro Area Data

For metro areas, we use the U.S. Office of Management and Budget’s (OMB) 2018 definitions of metropolitan statistical areas (MSA). The OMB defines a metropolitan statistical area as an area that has at least one city of 50,000 or more residents with surrounding areas that have a “high degree of social and economic integration” with the core city or cities such as commuting ties. MSA are made up of counties or county equivalents (e.g. parishes in Louisiana) and one county cannot be divided between metro areas or metro/non-metro areas. A full list of the MSAs and their component counties can be found here.

We then use microdata from the 2019 1-year ACS to calculate our estimates for the immigrant population in metro areas. When sample sizes are too small for some of the metro areas, we use microdata from the 2019 5-year ACS to generate our estimates.

County Data

For counties, we first use microdata from the 2018 5-year ACS to calculate our estimates for the immigrant population. When sample sizes are too small for some of the counties, we use estimates from the data portal of the U.S. Census Bureau to gauge immigrants’ share of a county’s total population.

Congressional Districts Data

Due to the irregular nature of U.S. congressional districts, analysis of each district was not possible using microdata from the 2017 5-Year ACS. Instead, we use estimates for hundreds of demographic and socioeconomic indicators published by the U.S. Census Bureau on its data portal. Using these estimates, we calculate all of the demographic and socioeconomic characteristics of each congressional district’s U.S.-born and immigrant population as listed on each district page.

Income, tax, and spending power figures were calculated using average household income estimates from the Census Bureau’s data portal and then weighted by congressional district to equal the total income, tax, and spending power figures calculated from microdata for each state. For Districts-At-Large, state data on household income, taxes, and spending power are used instead since the geographies are coterminous.

Demographics

Data points on the number, share, and age breakdown of both U.S.- and foreign-born residents are calculated using microdata from the ACS.

Entrepreneurship

The data on the number of self-employed immigrants and their business income comes from the ACS.

Income and Tax Contributions

Consistent with past Council research, we use the term “spending power.” _^[1] Here as elsewhere, we define spending power as the disposable income leftover after subtracting federal income, state, and local taxes from total annual household income.

Using the ACS microdata sample, we estimate the aggregate household income, tax contributions, and spending power of foreign-born households. A household is defined as a foreign-born household if the household head is foreign-born. We estimate state and local taxes using the tax rates estimates produced by Institute on Taxation and Economic Policy (ITEP) by state income quintiles. ^[2] For federal income tax rate estimates, we use data released by the Congressional Budget Office and calculate federal tax contributions using federal tax bracket determined with adjusted household income. ^[3]

Workforce

Educational attainment figures for the U.S.- and foreign-born ages 25 and up are calculated using microdata from the ACS. Using the age threshold of 25 allows us to examine the segment of the population most likely to have already completed their final level of educational attainment.

For states and metro areas, we use broad categories of industries—sometimes called the “2-digit” North American Industry Classification System (NAICS) codes, to classify and estimate which industry groups have the largest share of immigrant workers. All individuals 16 years old and above are included in these calculations. We exclude industry groups with small sample sizes of workers to avoid reporting estimates with large margins of error.

Estimated occupations with the largest share of foreign-born workers per state also follow the same restrictions—the universe is restricted to workers age 16 and above, and the occupations that fall under minimum threshold excluded.

STEM

We use the STEM (Science, Technology, Engineering, and Math) occupation list released by the U.S. Census Bureau to determine the number and share of foreign-born STEM workers from the ACS 1-year data. ^[4] Per U.S. Census classification, healthcare workers such as physicians and dentists are not counted as working in the STEM occupations.

Healthcare

For the share of foreign-born nurses and home health aides, we use microdata from the 2022 1-year ACS.

Housing

The data in the housing section comes from the ACS sample. Immigrant homeowners are defined as foreign-born householders who reported living in their own home. We estimate the amount of housing wealth held by immigrant households by aggregating the total housing value of homes owned by immigrant–led households. We also estimate the amount of rent paid by immigrant-led households by aggregating the rent paid by such families. We then calculate the share of housing wealth and rent that immigrant households held or paid compared to the total population. For characteristics of homeowners, a foreign-born new homebuyer is defined as a household with a foreign-born household head who owned and moved to the current residence within the last five years.

International Students

We use the number of international students in each state in the 2022-23 academic year from NAFSA, an organization representing professionals employed in the international offices of colleges and universities across the United States. NAFSA has developed an economic value tool and methodology that estimates the total economic benefit and jobs created or supported by international students and their dependents in each state. ^[5]The economic contributions include the costs of higher education along with living expenses minus U.S.-based financial support that international students receive.

Naturalization & Voting Power

Using data from the ACS sample, we estimate the number of immigrants who are eligible to vote, naturalized U.S. citizens, or eligible for naturalization. We define foreign-born eligible voters as naturalized citizens aged 18 or older who live in housing units. Persons living in institutional group quarters such as correctional facilities are excluded from the estimation. We identify immigrants who are potentially eligible for naturalization based on a set of criteria of eligibility for U.S. citizenship, such as age, English language proficiency, and length of stay in the United States.

Undocumented Immigrants

Using data from the ACS, we apply the methodological approach outlined by Harvard University economist George Borjas to arrive at an estimate of the undocumented immigrant population in the overall United States and individual states. ^[6]

It has been shown that census data tends to overestimate the number of naturalized citizens when compared to administrative records, especially for immigrants recently arrived or whose country of origin is Mexico. ^[7] For this reason, the immigration status of the foreign-born population is adjusted for misreporting in three ways. Foreign-born individuals who reported naturalization are reclassified as non-naturalized if the individual had resided in the United States for less than five years (as of 2022); or if married to a U.S. citizen, for less than three years; or if they reported their country of origin as Mexico.

Following this reclassification, we then use the following criteria to code foreign-born individuals as legal U.S. residents:Arrived in the U.S. before 1980

Naturalized citizen

Citizens and children less than 18 years old reporting that at least one U.S.-born parent

Recipients of Social Security benefits, Supplemental Security Income, Medicaid, Medicare, military insurance, or public assistance

Households with at least one citizen that received SNAP benefits

People in the Armed Forces and veterans

Refugees

Working in occupations requiring a license

Working in occupations that immigrants are likely to be on H-1B or other visas, including computer scientists, professors, engineers, and life scientists

Government employees, and people working in the public administration sector

Any of the above conditions applies to the householder’s spouse

Children of householders who are refugees or work in occupations that require a license or are likely to be on H-1B or other visas, as people with these statuses can generally apply for legal immigration status for their children.The remainder of the foreign-born population that do not meet these criteria are reclassified as undocumented. In part to adjust for misreporting in the ACS data noted above around reporting of naturalized citizens whose country of origin is Mexico, the make-up of the sample is then reweighted based on the country of origin to reflect the demographic make-up of undocumented immigrants based on DHS estimates, which are based on administrative records. ^[8]

Estimates regarding the economic contribution of undocumented immigrants and the role they play in various industries are made using the same methods used to capture this information for the broader immigrant population in the broader brief.

When estimating the tax contributions of undocumented immigrants, we follow the methodology detailed by Institute on Taxation and Economic Policy (ITEP). ^[9] For federal income tax rate estimates, we use data released by the Congressional Budget Office and calculate federal tax contributions using federal tax bracket determined with adjusted household income. ^[10]

Following the ITEP methodology, when calculating income and payroll taxes, the total amount paid is reduced by 40 percent to reflect a 60 percent contribution rate. This takes into account lower tax compliance rates among undocumented immigrants, but also the fact that some undocumented immigrants pay more income tax via withholding than they owe. When calculating sales and excise taxes, we recalculate the income brackets that undocumented households fall into, as it is recognized that approximately 15 percent of the income earned by undocumented immigrants goes towards remittances, leaving less to spend in their local communities. Corporate income tax rates are also recalculated to reflect lower levels of capital ownership.

Consistent with past American Immigration Council research, we use the term “spending power,” which we define as the disposable income left over after subtracting federal income, state, and local taxes from total annual household income.

DACA-Eligible Population

The data used to generate estimates comes from the ACS. As DACA recipients are legally allowed to work in certain occupations that undocumented immigrants cannot work in, we adjust our methodology to reflect such differences between undocumented immigrants and the DACA-eligible population.

Since DACA-eligible population is a subset of the total undocumented population, we apply the guidelines for DACA from United States Citizenship and Immigration Services (USCIS) to ACS microdata to restrict our data further. We determine an undocumented person to be DACA-eligible if the individual:

Was born after the second quarter of 1981;

Came to the United States before reaching his or her 16th birthday; and

Has moved to the United States by 2007.

While USCIS guidelines for DACA application also include restrictions on those who have criminal records, it is not possible to determine such information from the U.S. Census. We believe then, that our final numbers of the DACA-eligible population are the most reliable estimates that one can extrapolate from the U.S Census microdata.

Unlike past Council papers on income and tax contributions, this brief treats each DACA-eligible individual as a single taxpaying unit. This follows the lead of other groups, such as the nonpartisan Institute on Taxation and Economic Policy (ITEP), that have also sought to quantify the economic and tax contributions of this population. ^[11]

Similar to the Council’s other work on the economic contributions of immigrants overall, we estimate state and local taxes using the tax incidence estimates produced by ITEP. For federal tax rate estimates, we use data released by the Congressional Budget Office and calculate the federal tax contributions based on the CBO estimates for household federal tax incidence rates by income quintile.

We use the data from U.S. Citizenship and Immigration Services (USCIS) for the number of active DACA recipients and the number of people with DACA granted.^[12,13]

Refugees

Since nationally representative surveys that normally provide socioeconomic data to researchers do not include information on respondents’ immigration status beyond citizenship status, there is little quantitative data available on refugees and their socioeconomic characteristics after their resettlement. To address this, we use an imputation method, similar to the work of Kallick and Mathema^[14] as well as Capps et al,[15] to identify cases in microdata from the 2022 ACS that are likely to be refugees, using each foreign-born respondent’s country of birth and their year of arrival.

To identify the years that saw significant inflows of refugees from each country, we compare data from the U.S. Department of Homeland Security (DHS) and the U.S Department of State Bureau of Population, Refugees, and Migrations WRAPS database, showing yearly totals of refugee arrivals, with the ACS data showing how many people in the United States were born in each country and the year that each immigrated to the United States. We then assign refugee status to those born in a given country of origin who arrived during years when the number of refugee arrivals from that country according to DHS/WRAPS data exceeded 50 percent of the total population born in a given country who immigrated in each year.

What we find aligns broadly with what we know about refugee numbers in general. The vast majority of the refugees we identify came to the United States after 1980, after the Refugee Act, which established the foundation for modern U.S. refugee policy. Two groups are notably absent from our study: Cubans and Haitians. We chose to not include these groups as Cubans and Haitians have mainly been admitted through country-specific programs that confer upon them different benefits and statuses through different processes.

Inherently, this number and our method do not capture every refugee living in the United States in 2022. Refugee flows from countries that have other more traditional immigration pathways to the United States are not counted here, nor are countries that have sent relatively few refugees or immigrants to the United States overall, since such populations are difficult to pick up in surveys such as the ACS due to small sample sizes. However, while the counts of refugees may not match the administrative data on resettled refugees, we are confident that our method gives reliable estimates of the characteristics of refugee populations in the United States and are comparable to similar estimates done by other researchers in the field.

Temporary Protected Status Holders

To identify potential TPS holders, we follow the eligibility requirements from the United States Citizenship and Immigration Services (USCIS). As of 2022, there are 16 designated countries for TPS: Afghanistan, Burma (Myanmar), Cameroon, El Salvador, Ethiopia, Haiti, Honduras, Nepal, Nicaragua, Somalia, Sudan, South Sudan, Syria, Ukraine, Venezuela, and Yemen. After identifying the countries of origin for these individuals in the survey, we then use year of entry to determine whether they meet the requirement for continuous residence regulated by USCIS.

Similar to a paper by Center for Migration Studies (CMS) published in the Journal on Migration and Human Security, we include TPS holders in the estimates of undocumented immigrants though their status is comparable to other legally present non-citizens.

We use the same methodology to determine whether an individual is undocumented along with the TPS eligibility criteria described above to determine whether an individual is a potential TPS holder.

To estimate the total TPS-holding population, we apply weighting adjustments to estimates from the ACS. First, we use the data from the Congressional Research Service to capture to the largest extent individuals with approved TPS status in 2022 and match it to potential TPS holders identified in the 2022 ACS sample. We calculate the ratio of TPS holders by country of origin from the CRS to total potential TPS holders from the ACS for each of the 16 TPS designed countries. We then apply these ratios as weights to adjust for our final TPS population estimates.

Sources

New American Economy. 2017. “Power of Purse: How Asian Americans and Pacific Islanders Contribute to the U.S. Economy.” Available online.
Institute on Taxation and Economic Policy. 2018. “Who Pays? A Distributional Analysis of the Tax Systems in All 50 States (6th edition).” Available online.
Congressional Budget Office. 2022. “The Distribution of Household Income and Federal Taxes, 2019.” Available online.
U.S. Census Bureau. 2018. “STEM, STEM-related, and Non-STEM Occupation Code List 2018.” Available online.
NAFSA. 2023. “International Student Economic Value Tool.” Available online.
Borjas, George J. 2016. “The Labor Supply of Undocumented Immigrants.” NBER Working Papers 22102, National Bureau of Economic Research, Inc. Available online.
Jennifer Van Hook and James D. Bachmeier, “How Well Does the American Community Survey Count Naturalized Citizens?,” Demographic Research 29, no. 1 (2013): 1.
Bryan Baker and Robert Warren, “Estimates of the Unauthorized Immigrant Population Residing in the United States: January 2018–January 2022,” U.S. Department of Homeland Security, April 2024. Available online.
Carl Davis, Marco Guzman, and Emma Sifre, “Tax Payments by Undocumented Immigrants,” Institute on Taxation and Economic Policy, July 30, 2024. Available online.
See “The Distribution of Household Income and Federal Taxes, 2019.”  Congressional Budget Office. 2022.
Hill, Misha E. and Meg Wiehe. 2017. “State and Local Tax Contributions of Young Undocumented Immigrants.” Institute on Taxation and Economic Policy. Available online.
U.S. Citizenship and Immigration Services (USCIS). “Count of Active DACA Recipients by Month of Current DACA Expiration As of December 31, 2023.” Available online.
USCIS. “Number of Form I-821D, Consideration of Deferred Action for Childhood Arrivals – Requests by Intake and Case Status, by Fiscal Year, Aug. 15, 2012 – December 31, 2023.” Available online.
Kallick, David D. and Silva Mathema. 2016. “Refugee Integration in the United States.” Center for American Progress. Available online.
Capps, Randy and Kathleen Newland, et al. 2015. “The Integration Outcomes of U.S. Refugees.” Migration Policy Institute. Available online.