My decade-by-decade U.S. census manuscript directories summarize key points about each decennial census, provide direct links to each decennial census collection on FamilySearch (FREE) and Ancestry.com ($), and link to essential reference tools for deeper analysis of each census.
The census manuscripts are the original handwritten forms filled out by the census taker for each federal decennial census when the census taker went door to door. These pages contain names and personal information.
Ten years later in 1952 the two agencies established a 72-year embargo before the remaining census manuscripts could be released to public researchers, likely for privacy reasons since the records contain personally identifiable information (Kratz, Aprill 2022). NARA releases each decennial census for public research access 72 years from that census's Census Day. A FOIA (Freedom of Information Act) request must be filed to gain access to original records that are younger than 72 years old.
A researching reviewing an original U.S. census manuscripts
in the reading roomat the main NARA facility in Washington, D.C., 1940.
Public domain photo from NARA.
The Census Bureau started transferring custody of census records to the U.S. National Archives and Records Administration (NARA) in 1942, including the bound paper copies of 1790–1870 population schedules as well as other non-population schedules. They later transferred over the original bound paper copies of the 1880 census population schedule and what remained of the 1890 census.
The original paper copies of the 1900 - 1970 censuses are no longer available. The Census Bureau destroyed the originals after microfilming them. While the 1880 census was transferred over to NARA in paper form, NARA microfilmed it and then gave the paper copies to respective state archives and libraries, and other institutions. Later census manuscripts have been transferred from the Census Bureau to NARA in electronic format, not in their original paper format Kratz, February 2022).
References
Kratz, J. (2022, February 17). Census Records Come to the National Archives. Pieces of History, U.S. National Archives and Records Administration. https://prologue.blogs.archives.gov/2022/02/17/census-records-come-to-the-national-archives/
Kratz, J. (2022, April 1). Public Access to Census Records at the National Archives. Pieces of History, U.S. National Archives and Records Administration. https://prologue.blogs.archives.gov/2022/03/17/public-access-to-census-records-at-the-national-archives/
Map Guide to the U. S. Federal Censuses, 1790-1920 by 
The Census Book by