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U.S. Census

Explaining how U.S. Census data is used, how it impacts Illinois, and more.

What is the U.S. Census?

The U.S. Census is an official count of the population of the United States that takes place once every ten years (the “Decennial Census.”) The primary purpose of the Census — mandated by the U.S. Constitution — is to ensure that each state is proportionately represented in Congress through the U.S. House of Representatives.

The 435 seats in the U.S. House are allocated to the 50 states based on their population. The U.S. Senate, on the other hand, includes two lawmakers from each state regardless of population. Because U.S. House members generally represent smaller geographic regions than U.S. senators, they can more closely advocate for the interests of individual citizens.

This legislative structure both ensures that the interests of individual states are balanced against one another and that each state has a platform upon which its representatives can advocate for its people and economy. All legislation for raising revenue must originate in the U.S. House of Representatives; therefore, House members are in a unique position to advocate for vital state interests, such as federal fund distribution — over $400 billion in federal funds allocated across states each year1 — and interstate commerce.

The Census also dictates the in-state redistricting of legislative bodies and the distribution of Electoral College votes for the U.S. presidential election.2

In addition to this, the Census tracks shifting demographics in the country. For instance:

  • How many people are moving out of, or into, a particular city3 ,
  • How many children live in each household, and
  • What the average income of each household is.4

1 Marisa Hotchkiss, Jessica Phelan, Uses of Census Bureau Data in Federal Funds Distribution, United States Census Bureau, (September 2017).

2 National Archives and Records Administration, U.S. Electoral College, Distribution of Electoral Votes.

3 Central Statistics Office, Who uses Census data?

4 United States Census Bureau, Topics: Income & Poverty.

Who conducts the U.S. Census?

The U.S. Census is conducted by the United States Census Bureau.

The U.S. Census Bureau is part of the U.S. Department of Commerce. It is overseen by the Economics and Statistics Administration (ESA) and currently employs about 4,285 staff members.1 The Director of the Census Bureau is appointed by the President of the United States of America.

The Census Bureau has a budget request of 3.8 million for the Fiscal Year 2019 which reflects planned increases of $2,400.9 million.2

Despite Congress allocating $2.814 billion for the Census Bureau in FY20183 , many argue the U.S Census Bureau is underfunded.4 Former Census director John Thompson has stated that the Bureau “has been underfunded by about $200 million” since 2012, preventing them from conducting a census that delivered an accurate count.5

Alongside the Decennial Census, the Census Bureau also conducts a variety of other surveys that collect information about the “Nation’s key economic indicators,” all of which are used to determine the allocation of $400 billion in federal funds on an annual basis.6

The Census Bureau also conducts other surveys:

  • The Economic Census, which measures American Businesses and the economy every five years;
  • The Census of Governments, which measures public finance and public employment in local government; and 
  • The American Community Survey (ACS).

The ACS, unlike the Decennial Census that takes place every ten years, is an ongoing survey that is updated on a yearly basis and generates data which leads to conclusions about how the government is performing, what it must do to perform better, and which specific areas or regions it must divert a portion of state or federal funds to.7

The ACS is essentially a survey of American households. It collects information on a wide array of topics including education, occupations, citizen voting-age population, the number of people receiving healthcare, the number of people who own or rent homes, marital status, and so forth. The survey’s findings then help determine how more than $675 billion in federal and state funds is distributed each year.8 For instance, state and city officials, using data furnished by the ACS survey, are able to make informed decisions about which region requires a new school or a new lunch program, or which community is in need of improved medical or emergency services.9

1 United States Census Bureau, About the Bureau, Who We Are.

2 United States Census Bureau, Fiscal Year 2019 Summary

See, Minnesota Council of Foundations, Congress Finally Steps up to Meet The Challenge of 2020 Census Funding, (March 22, 2018); Arloc Sherman, After Budget Deal, Policymakers Should Boost 2018 Funding for the 2020 Census, Center on Budget and Policy Priorities (Feb 16, 2018).

See, Robert Shapiro, The 2020 Census may be wildly inaccurate—and it matters more than you think, The Brookings Institute, (Aug 31, 2017); Alexis Farmer, Funding the Census, Brennan Center for Justice; Terry Wing, Budget, staffing shortages at Census could threaten 2020 count in rural areas, Federal News Network, (Jan 15, 2018); NPR: National Public Radio; The Risks Of An Underfunded Census, (May 13, 2017); The Census Project, The Cannibalization of the Census Bureau, (Dec 18, 2017).

5 Chase Gunter, Thompson dishes on Census concerns, needs for catch-up, The Business of Federal Technology (FCW), (Jul 26, 2017).

6 United States Census Bureau, U.S. Census Bureau Strategic Plan FY 2013 – 2017.

7 Catherine Rampell, The Beginning of the end of the Census?, The New York Times, (May 19, 2010).

8 United States Census Bureau, American Community Survey (About).


What is U.S. Census data used for?

Besides apportioning seats to the U.S. House of Representatives, U.S. Census data is used for:

  • Redistricting purposes in states,
  • School district assignment areas,
  • Allocating federal funds across states for building new roads, schools, and employment opportunities,
  • Public health, and
  • Transportation.

In addition to this, it is also used to identify population shifts and demographics based in age, race, and ethnicity.

When does the U.S. Census take place?

The Census Bureau conducts the U.S. Census—a full population count of the country—every 10 years in years ending with a zero. The process therefore, is now known as the “Decennial Census.”1

1 Recurring every 10 years.


When is the next U.S. Census?

The next U.S. Census will be conducted in 2020.

While the results of the U.S. Census will be processed and sent to the President by December 31, 2020, the Census Bureau began the data collection process as early as September 2015 when it began establishing “where to count”— a process through which the Bureau collects addresses of all the places where people could live.1

1 United States Census Bureau, 2020 Census Operational Plan, A New Design for the 21st Century, p. 8, (September 2017).

How will the 2020 Census be conducted?

For the 2020 Census, the Census Bureau is testing new technology and moving in a different direction in an effort to improve accuracy. Here are their steps:

1. Establish where to count: The Census Bureau creates an address list of all the places where people could live. For the 2020 Census, the Bureau began this process in September 2015 and continued to update its list over the years using resources such as “the U.S. Postal Service, tribal, state, and local governments, satellite imagery, and third-party data providers.”1

2. Motivate people to respond: In an attempt to counter declining response rates to surveys and censuses over the years, the Census Bureau is largely shifting its focus to collecting answers online. For 2020, the Bureau has launched a digital-media-centered campaign with a heavy focus on targeted advertisements to motivate people to respond to the Census.2 On March 2020, the Census Bureau will send out a letter with information to some households, urging them to take the survey online, while other households will receive a paper survey. This process will depend on “demographic characteristics and internet connectivity”3 of households in certain geographic areas. The official “Census Day” is April 1, 2020.4

3. Count the population: Beginning March 2020 and leading up to April 1 (Census Day), the Census Bureau will send letters, “it’s not too late” postcards, and questionnaires to non-respondents. If certain households still fail to respond to the questionnaire, the Census Bureau will send field workers to collect responses in person. In doing so, it will use data provided by government administrative records and third-party sources to “identify vacant households” and “determine the best time of day to visit a particular household”5 in order to avoid wasting resources.

4. Release Census results: The Census Bureau will release the Census results to the President for the purposes of apportionment by December 31, 2020. The results will be released to the states for the purposes of redistricting by April 1, 2021, and will be released to the general public by December 2021.6

Road to the 2020 Census: Three Years Until Census Day

[Source: U.S. Census Bureau]

1 United States Census Bureau, 2020 Census Operational Plan, A New Design for the 21st Century, p. 8, (September 2017).

2 Id.

3 Census Outreach, Census Timeline.

4 Id. Also see, United States Census Bureau, The 2020 Census at a Glance.

5 U.S. Census Bureau, supra Note 2.

6 Id.

Do individual states conduct Censuses?

Not anymore.

Some states used to conduct censuses — generally on years ending in “5” (2005, 2015, etc.) to complement the federal census — and those records can be helpful to genealogy researchers. The last state census was taken in 1945, according to the Census Bureau.1

1 United States Census Bureau, History, State Censuses.

What other entities use the U.S. Census information?

U.S. Census information is used by government departments and agencies, non-profit organizations, regional and local authorities, businesses, schools, local community groups, healthcare professionals, students, and researchers.1

1 Central Statistics Office, Who uses Census data?

Do I have to respond to the U.S. Census?

Yes. The U.S. Census counts every resident in the United States. This includes both “foreign born” and “native born” residents.

The U.S. Census Bureau classifies “native born” residents as anyone who is a U.S. citizen at birth; born in the United States; born in Puerto Rico; born in a U.S. Island Area (e.g., Guam); or born abroad of U.S. citizen parent(s).1

The Census Bureau also collects data from all other residents, regardless of legal status.

A “foreign born” resident is anyone who is not a U.S. citizen at birth. This includes: “Naturalized U.S. citizens, lawful permanent residents (immigrants), temporary migrants (such as foreign students), humanitarian migrants (such as refugees and asylees), and unauthorized migrants.2 Unauthorized immigrants are “implicitly” added in the Census when the total foreign-born population is estimated.3

By law, Americans must respond to the U.S. Census Survey.4 While an adult who refuses to answer a Census Bureau survey or willfully gives false answers may be fined, no one has been prosecuted for a failure to respond since the 1970 Census.5

1 United States Census Bureau, The Foreign-Born Population in the United States.

2 United States Census Bureau, Foreign-Born Population (About).

3 Id.

4 Title 13, U.S. Code, Sections 141 and 193.

5 W. Gardner Selby, Americans must answer U.S. Census Bureau survey by law, though agency hasn't prosecuted since 1970, Politifact Texas, (Jan 9, 2014).

Does the U.S. Census ask about an individual’s citizenship?

The first time the Census Bureau included the citizenship question in its questionnaire was in 1820.1 After that, the question made sporadic appearances in questionnaires throughout the 1800s. For instance, the citizenship question was not included in the 1840 or 1850 Census, but was included in 1870; however, the question was only asked of men 21 or older. The 1880 Census did not include a citizenship question, but every Census conducted from 1890 to 1950 did.

Fast forward to the year 2000: The Census Bureau included the citizenship question in its ACS survey—an annual survey that counts a smaller number of households—and only asked one-sixth of the population the question in the Decennial Census.2

It should be noted, that while the ACS survey asks whether an individual is a citizen or not (by birth or naturalization), it does not ask whether an individual is a legal or illegal immigrant.3

In the last U.S. Census conducted—the 2010 Census—the citizenship question was not included (however, it was still included in the ACS survey).

For the 2020 Census, the Census Bureau is planning to ask the citizenship question. According to the Pew Research Center, this is the first time since 1950 that the Census Bureau is planning to ask everyone living in the United States whether they are citizens.4

The request to include the question was set forth by the Justice Department, which said it wants the citizenship question to be reintroduced so it can collect more detailed information about the citizen voting-age population (citizens 18 or older).

The Justice Department said the information would help it prevent racial discrimination in voting under Section 2 of the Voting Rights Act. Specifically, it said the data could help ensure that minority votes are not diluted through redistricting that splits those voters among multiple districts when they could form a majority in a single district.

Proponents of the citizenship question say it does not pose a problem as the question has already been included in the ACS survey since 2000 and because responses to the survey remain anonymous.5

Those who oppose the question have major concerns about whether the survey responses are anonymous.6 Additionally, there are concerns that including this question will prevent people—primarily, minorities and immigrants—from responding to the survey at all, which in turn will result in an inaccurate count of the population.7

1 Jason Richwine, A History of the Census Bureau's Birthplace and Citizenship Questions in One Table, Center for Immigration Studies, (June 8, 2018).

2 Id.

3 Miriam Jordon, If Census Asks About Citizenship, Some Already Have an Answer: No Comment, The New York Times, (March 27, 2018).

4 D’vera Cohn, What to know about the citizenship question the Census Bureau is planning to ask in 2020, Pew Research Center, (March 30, 2018).

5 Lynn Vavreck, Why Asking About Citizenship Could Make the Census Less Accurate, The New York Times, (Jan 19, 2018).

6 Miriam Jordon, If Census Asks About Citizenship, Some Already Have an Answer: No Comment, The New York Times, (March 27, 2018).

7 Vavreck, supra note 5.

Can I skip the 2020 U.S. Census citizenship question?

If you skip the citizenship question, you will still be counted in the upcoming U.S. Census, according to this report.

However, refusing to answer a U.S. Census question or intentionally giving an incorrect or false response can lead to a fine under federal law. Additionally, submitting an incomplete Census questionnaire may also result in an in-person visit to your home from Census Bureau workers.1

1 Hansi Lo Wang, Skipping The 2020 Census Citizenship Question? You'll Still Be Counted, NPR: National Public Radio, (April 19, 2018).

What is the importance of obtaining an accurate Census count?

If people fail to respond to the Census because of the citizenship question or for any other reason, it could lead to an undercount. That is, large groups of people would not be counted in the total population of a state. As a result of this undercount, the state’s population could appear smaller than it is. Since information collected through the Census determines how federal funds are allocated to states based on population, certain states could lose a significant amount of money.1

Counting for Dollars 2020, a study by George Washington University Research Professor Andrew Reamer2 , calculates the direct impact a Census undercount can have on the allocation of federal funds to states and the impact that has on a state’s ability to improve the lives of its citizens. The study focuses on five programs that are administered by the U.S. Department of Health and Human Services (HHS): Medicaid, the Children’s Health Insurance Program, Title IV-E Foster Care, Title IV-E Adoption Assistance, and the Child Care and Development Fund.3

Federal and state spending for each of these programs is dependent on information collected through the Census. Specifically, the study notes, the Department of Health and Human Services applies a “Federal Medical Assistance Percentage”4 that is based on the 2010 Decennial Census population count. It then uses that percentage to determine how much money (a collection of payments and reimbursements) will be allocated to each program. For fiscal year 2015, the study estimated a median loss per person missed of $1,091.

This means, that for each person who was not counted in the 2010 Census, the median state suffered a loss of $1,091. Some states suffered a lower loss ($533 for Utah), while some states suffered a much higher loss per person ($2,309 for Vermont).5

In addition to this, states could lose House seats and Electoral College votes.

1 Andrew Reamer, Counting for Dollars 2020, The Role of the Decennial Census in the Geographic Distribution of Federal Funds (Report #2: Estimating Fiscal Costs of a Census Undercount to States), The George Washington University Institute of Public Policy, p. 3, (March 19, 2018).

2 Id.

3 Id.

4 Id.

5 Id.

How does the Census population count impact Illinois?

Illinois lost a net 33,703 residents in 20171 , and dropped from the fifth largest state to the sixth, overtaken by Pennsylvania. Since the population of each state dictates its representation in the U.S. House, an Illinois population decline in the 2020 Census could cost it one or two seats in Congress.2

That drop in congressional representation would also mean a loss of votes in the Electoral College, which elects the president. A population drop would also reduce Illinois’ share of various types of federal funding.3

According to Counting for Dollars 2020, a study by Research Professor Andrew Reamer, for each person not counted in Illinois during the 2010 Census, the state lost $953.4 The study also points out that if the 2020 Census results in an undercount of the population, Illinois, amongst other states, could face much drastic fiscal consequences than those presently mentioned in the report.5

1 Editorial Board, Editorial: Census 2020: High stakes for Illinois, Chicago Tribune, (Jan 19, 2018).

2 Id.

3 Id.

4 Andrew Reamer, Counting for Dollars 2020, The Role of the Decennial Census in the Geographic Distribution of Federal Funds (Report #2: Estimating Fiscal Costs of a Census Undercount to States), The George Washington University Institute of Public Policy, p. 3, (March 19, 2018).

5 Id. at 5