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Where Does the Data Come From?

Census Data


The United States Census takes place every 10 years, most recently in 2020. Due to the COVID-19 pandemic, there have been concerns about the quality and quantity of data collected, as well as whether target deadlines would be met.

Why This is Important

It is legally required that redistricting maps meet equal population criteria, which requires census data. Besides being used in redistricting, data collected by the Census is used to allocate billions in federal funding and determine the apportionment of Congressional seats. Importance of the Data

Who is surveyed?

The Census sends surveys to all U.S. residential structures to count citizens, non-citizen legal residents, non-citizen long-term visitors, undocumented immigrants, and those experiencing homelessness. “Residential structures” include group housing such as correctional facilities, college dormitories, military barracks, and retirement homes.

When is data collected?

The Census Bureau started its planning process in 2013 and officially began the count on January 21, 2020. Its official deadline to deliver apportionment counts to the President was December 3, 2020. By April 2021, the Census Bureau is expected to send redistricting counts to the states, which will use those data to redraw legislative districts based on population changes. Important Dates 2020 Census Delays and the Impact on Redistricting What information is collected? Census surveys ask about the number of people living in the same residence, how they are related, and collect information on each member of the household. Questions include age, sex, race, Hispanic origin. There is no citizenship question on the 2020 Census. Questions Asked on the Form

How is this data collected? The Census Bureau sent out invitations to most households to complete their responses online, by phone, and by mail. Field workers then followed up with those who did not respond in person or over the phone. How is this data processed? Between collection and delivery of data, the Census processes data through quality control checks, removal of personally identifiable information, combining of data from different Census programs, imputation, and differential privacy. Many of these processes are aimed at ensuring accuracy and privacy. Miscounts can mean the loss or gain of a Congressional seat for the next decade. In addition, the Census must guarantee the privacy of those individuals it relies on to provide data so it can fulfill its goal of enumeration. [Link to Angel’s research report] Where can this data be found?