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What You Need to Know About Census Data

Election Administration

The United States Census offers a wealth of data on the demographics of our country. This also includes data on election behaviors and data that is used in election processes. The EAC is taking a closer look at what the census is and how it impacts elections.  

What is the United States Census? 

Every 10 years, the United States Census Bureau conducts a survey of the entire American population, gathering both the total number of residents, as well as detailed information about a representative sample. This count is required by Article One, Section Two of the United States Constitution, and the first census was held in 1790. While the Census Bureau’s techniques for counting have changed dramatically over the intervening centuries, the importance of this count to the American people and our government has not. 

How is census data used for elections? 

Everyone likely knows that the population count conducted by the census is used to allocate members of the United States House of Representatives by state. This is based on a formula that strives for roughly proportionate numbers, with each state guaranteed at least one member, and additional members designated based on population. Because Representatives cannot be fractionally split across states, this results in some members of Congress representing as few as 527,000 voters, and others as many as 994,000, with the average member having 712,000 constituents. This distribution of members of Congress also has a direct impact on how many votes each state has in the Electoral College – the body that formally elects the president every four years. 

As part of this “apportionment,” the census data is also used to draw the lines that delineate the boundaries of our election districts, a process known as redistricting. Then, in turn, election officials draw the lines that make up the precincts in which voters cast their ballots, known as “reprecincting.” Ensuring that every district has approximately the same number of people and, in turn, that precincts are equally divided, helps voters have equivalent voting experiences as everyone else in their area. It also ensures that each representative in a state represents the same number of voters as any other representative in that state. 

Additionally, the data gathered by the Census Bureau serves many purposes beyond helping us decide who our representatives are. 

This includes use by federal, state, and local governments to decide where to spend money and dedicate other resources. For example, federal money for schools, roads, and other public facilities is distributed to communities, in part, based on their proportion of the population. For elections, the U.S. Election Assistance Commission uses the census data to distribute HAVA grant funds based on a formula that relies on a state’s proportion of the nation’s voting-age population. 

The Census Bureau also gathers detailed information regarding who lives in our communities, including data on the racial and ethnic makeup of our neighborhoods, the languages our residents speak, and other demographic characteristics. Racial and ethnic information is key in ensuring compliance with the Voting Rights Act, by providing relevant information officials can use to draw districts that permit minority voters to elect candidates of their choice. Election officials can use this information to tailor the communications they produce, and perhaps more importantly, ensuring that their ballots and other election materials comply with the language access needs of their communities, as mandated by Section 203 of the Voting Rights Act

For information on redistricting for local election officials, please visit EAC’s Local Election Official’s Guide to Redistricting.  

For information on how EAC uses census data for the distribution of HAVA grants, visit EAC’s FAQ on Grants

For more information on language resources and compliance with Section 203 of the Voting Rights Act, visit EAC’s Language Access Resource Page