Weeks before the 1980 census officially began, the Federation for American Immigration Reform launched its campaign to exclude unauthorized immigrants from population counts that, according to the Constitution, must include the "whole number of persons in each state." Ernie Leyba/The Denver Post via Getty Images hide caption
The 2020 census has been disrupted by the coronavirus pandemic, historic hurricane and wildfire seasons, last-minute schedule changes, and President Trump's call to leave unauthorized immigrants out of a key census count. David L. Ryan/The Boston Globe via Getty Images hide caption
Commerce Secretary Wilbur Ross, who oversees the Census Bureau, waits for a House Oversight and Reform Committee hearing to begin in Washington, D.C., in 2019. In July, Ross directed bureau officials to speed up the 2020 census to end counting a month early, on Sept. 30. Andrew Harrer/Bloomberg via Getty Images hide caption
U.S. Census Director Steven Dillingham departs a Sept. 17 news conference in Phoenix. The Trump administration is facing two federal lawsuits over its last-minute decision to cut the 2020 census schedule short. Ross D. Franklin/AP hide caption
The Trump administration has announced its third new political appointee in less than two months at the U.S. Census Bureau, which is headquartered in Suitland, Md. Claire Harbage/NPR hide caption
Demonstrators rally outside the U.S. Supreme Court in April 2019 to protest against the Trump administration's efforts to add the now-blocked citizenship question to the 2020 census. J. Scott Applewhite/AP hide caption
President Trump departs a July 2019 press conference on the census with U.S. Attorney General William Barr (center) and Commerce Secretary Wilbur Ross in the White House Rose Garden. Alex Wong/Getty Images hide caption
Starting July 23, the Census Bureau says door knockers will make in-person visits to households that have not yet filled out a 2020 census form in parts of Connecticut, Indiana, Kansas, Pennsylvania, Virginia and Washington. Andrew Harrer/Bloomberg via Getty Images hide caption
The Trump administration announced two new political appointees Tuesday at the U.S. Census Bureau, which is headquartered in Suitland, Md. Claire Harbage/NPR hide caption
A sign encourages newly sworn-in U.S. citizens to register to vote outside a naturalization ceremony in 2019 in Los Angeles. After failing to get the now-blocked citizenship question on the 2020 census, the Trump administration is continuing to gather government records to produce citizenship data for redistricting. Mario Tama/Getty Images hide caption
The coronavirus pandemic is forcing the U.S. Census Bureau to suspend for two more weeks the hiring of 2020 census workers and in-person visits in remote communities and areas recovering from natural disasters. Andrew Harrer/Bloomberg via Getty Images hide caption
A bus stop with a poster promoting the 2020 census sits empty in New Rochelle, N.Y., a New York City suburb where National Guard members were sent to try to slow the spread of the coronavirus outbreak. Yuki Iwamura/Bloomberg via Getty Images hide caption
Demonstrators rally in Washington, D.C., in April 2019 against the now-blocked citizenship question that the Trump administration tried and failed to get on the 2020 census forms. Mandel Ngan/AFP via Getty Images hide caption