How the Census Works

How Does the Census Process Actually Work?

1980 Census 1980 Census
During the 1980 census, most people received and replied to the census by mail, a practice that started in 1960. Door-to-door visits still continued for hard-to-reach populations. U.S. Census Bureau

Collecting and reporting census data is a multiyear process. The 2020 census actually began back in March 2018, when the bureau officially submitted its 2020 census questions to the United States Congress [source U.S. Census Bureau]. The new batch of eight questions includes one about citizenship, which hasn't been asked in any form since 1950. That citizenship question was challenged and the Supreme Court has ruled against it (see sidebar), though President Trump has threatened to delay the Census because of this [source: CNN].

Census workers were also hired throughout 2018 and 2019 to begin the work of canvassing neighborhoods — both online using satellite images and in person — to verify addresses. During the summer of 2019, state governments will also be tasked with providing the Census Bureau with the locations of all known "transitory" housing locations, such as RV parks, campgrounds, carnivals, and long-term stay hotels and motels.

Data collection for the 2020 census will began in earnest on Jan. 21, 2020, when census workers will travel by bush plane and snowmobile to reach Toksook Bay, Alaska, estimated population 661 [source: U.S. Census Bureau, Wang]. Since 1990, rural Alaskan villages have been the first to be counted since this needs to happen before the spring thaw makes travel impassable [source: Miller].

The rest of the country will receive their first census invitation in mid-to-late March 2020 (March 12-20). For 95 percent of households, the first invitation will come in the mail, but it won't include a paper census questionnaire. Instead, households will be directed to a web address to complete the census online. The delivery will be staggered so as to space out the numbers of recipients going online to fill out the census form. For the 2020 census, paper questionnaires will only be delivered to households that don't receive mail at a physical location (people who get their mail in a P.O. box, for example, or people affected by a natural disaster) [source: U.S. Census Bureau]. Those paper questionnaires will be delivered directly by census workers.

Completed census forms will officially be due on April 1, 2020 — Census Day. From May through July, hundreds of thousands of census workers will comb the streets to collect data from households that failed to respond by mail. In 2010, only 68 percent of forms were received by April 16 [source: Roberts]. In the end, 74 percent responded by mail.

Throughout the spring and summer of 2020, the Census Bureau will also conduct special operations to count people with no fixed address or who live in dormitories, nursing homes, prisons, shelters, trailer parks, transient housing and other group or nonstandard housing.

From July through December, the Census Bureau will crunch numbers to accurately record and analyze the new population data. By Dec. 31, 2020, the bureau is required by law to report the new Congressional apportionment numbers to the president. The bureau will have until April 1, 2021, to provide each state with detailed redistricting data [source: U.S. Census Bureau].