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NARA expects to digitally release the 1950 population census schedules for researcher use on April 1, 2022, which is 72 years after the official 1950 census day of April 1, 1950. This is the 24th in a series of blog posts on the 1950 census.


Earlier this year the blog post, “1950 Census:  It Took More Than 148,000 People to Make it Happen!” examined the training schedule - shown below - that preceded the taking of the 1950 census.


Technical Training Program - 1950 Census:  Training Planning Schedule

Item, "Technical Training Program - 1950 Census" from "[Folder 2] Flow Charts, 17th Decennial Census, 1950" (NAID 195980236), in series "Narrative Histories, Committee Minutes, and Procedural Manuals Primarily Relating to the 17th Decennial Census" (NAID 5634057).


Some 26 chief instructors spent two weeks in Washington, DC, learning everything there was to know about the forthcoming census.  Those 26 then taught 400 instructors the same material at classes held at Washington, DC (actually Suitland, Maryland); Saint Louis, Missouri; and San Francisco (actually Alameda), California.  Of the 400, it was expected that 360 would be available to teach the 8,300 crew leaders who ultimately instructed 140,000 enumerators how to do the job.


Who were the men and women that attended “instructors schools”?  It’s not a secret.  Their names are in a file called “Rosters of Persons Attending Classes” (National Archives Identifier 206240427).  Most were employees of the Census Bureau or the Department of Agriculture, but there were also a few university personnel.  The rosters usually indicate each person’s name; employer; city and state of residence; location of training school; and the dates attended.  The lists include a few names crossed out that indicates persons who planned to attend but did not.  Some people are on more than one list. The image below shows one out of 31 pages in this file.


Instructors Class Starting Feb. 20, 1950, St. Louis, MO

(Image 3 of 31 from "Binder 60-C - Rosters of Persons Attending Instructor Classes (NAID 206240427); series "17th Decennial Census Reference Materials" (NAID 2990119); Record Group 29, Records of the Bureau of the Census.

Instructors class starting Feb. 20, 1950, Saint Louis, Missouri



This file of rosters of persons attending instructor classes has been digitized and is available for researcher use in the National Archives Catalog at  Perhaps you'll find a name of interest to you.

NARA expects to digitally release the 1950 population census schedules for researcher use on April 1, 2022, which is 72 years after the official 1950 census day.  This is the 23rd in a series of blog posts on the 1950 census.


6.18 miles.  That’s how much paper there was.  When the enumerators finished their work, all of the Forms P1, 1950 Census of Population and Housing, were sent to Census Bureau headquarters in Suitland, Maryland, a suburb of Washington, DC.  There the data was tabulated, analyzed, and published in many formats.  The paper P1 forms took a massive amount of space:  32,000 cubic feet.  The image below shows a modern cubic foot box:

Modern cubic foot box


The modern cubic foot box measures 12.25 inches by 15.25 inches by 10 inches, for a volume of about 1,868 cubic inches.  Those dimensions enable the box to accommodate both letter size paper/folders (front to back) or legal size paper/folders (side to side).  In contrast, a perfect cubic foot would measure 12 inches x 12 inches by 12 inches for a volume of 1,728 cubic inches. 


A row of 32,000 cubic foot boxes would be 32,666 feet long, or a little over 6.18 miles.  That’s a lot of paper.


In 1952, Census Bureau technicians microfilmed the population information on the front side of the Forms P1, 1950 Census of Population and Housing.  This is the microfilm set now known as NARA Microfilm Publication T628, Seventeenth Census of the United States, 1950 (6,373 rolls), that will provide the bulk of the records for the 1950 census release on April 1, 2022.  Instead of 32,000 boxes of paper, the 6,373 35mm microfilm rolls would fit in 79 modern cubic foot boxes (assuming 81 rolls per box).  That’s a huge difference in the amount of physical space.  The cost of microfilming was estimated at about $72,000 (1952 dollars) for the camera original negative plus one positive copy – or about $738,193 today (2021 dollars).  The image below shows a target (identification) sheet that begins each microfilm roll:


Researchers who remember looking at older census records on microfilm (before the “online” era) know that census microfilm is typically arranged by state, then by county, then by minor civil division, then by Enumeration District (ED) number.  Thus, Roll 1 of population census microfilm typically began with Autauga County, Alabama--the first county alphabetically in the first state alphabetically.


When the 1950 census was microfilmed in 1952, however, an entirely different approach was taken.  The P1 forms were apparently filmed in the order in which the Census Bureau was done using them for data tabulation purposes.  Thus, Autauga County, Alabama, ended up on Roll 2492 instead of Roll 1 where one would have traditionally found it.  A state-by-state “county level” view of the microfilming “order” was provided by the Bureau of the Census to the National Archives as the “Index to the Microfilm of the 1950 Decennial Census” (National Archives Identifier [NAID] 196015600), of which the first page for Alabama is shown below:


Most 1950 census microfilm rolls have a few EDs from one county, and then another, and then another, and so forth, often from different states.  There is no coherent order.  Fortunately, researchers won’t need to know what “microfilm roll” to look for when the census opens for public use on April 1, 2022.  Part of NARA’s preparation includes identifying the order in which each Enumeration District appears on each roll of microfilm and identifying all of the images (pages) for each ED.  The special NARA website dedicated to the 1950 census will enable researchers to search by state, county, ED numbers, and possibly in other ways.  (The URL for the website will be announced at at later date.)

The Census Bureau did not microfilm the housing data on the reverse side of the Form P1, 1950 Census of Population and Housing.  If the reverse side had been filmed, the number of microfilm rolls would have doubled to 12,746 rolls.  In 1961, the National Archives approved the destruction of the original paper 1950 census forms because “the essential value of the population schedules are preserved” on microfilm “and the data contained on the housing schedules are adequately summarized in publications of the Bureau of the Census.”  Due to the confidential nature of the census schedules, the housing data could not “be used by nongovernment researchers for further analysis” for many decades and it was thought that “by the time the schedules could be made available to scholars, the information about individual dwellings would have insufficient value to require the retention of these records,” according to NARA Disposition Dossier II-NN-3467 (NAID 7461357).  Certain collections of P1 forms that the Bureau retained in 1961 for further studies were disposed in 1963, according to NARA Disposition Dossier NN-163-128 (NAID 7461357).  Thus, the paper P1 forms came to the end of their lifecycle.

NARA expects to digitally release the 1950 population census schedules for researcher use on April 1, 2022, which is 72 years after the official 1950 census day.  This is the 22nd in a series of blog posts on the 1950 census.


It’s good advice even with today’s digital mapping applications that can give verbal directions to help you get to your destination.  “Your Map is Your Guide - Use It!” is also the title of Section IV-A of the “Enumerator’s Workbook” of October 1949 (National Archives Identifier 205683226).


During 1947 to 1949, the Census Bureau conducted “dress rehearsals” of the 1950 census by testing enumeration forms and instructions in “pretest” enumerations in various parts of the country.  (No, the pretest enumeration forms do not exist.). Census staff learned from the experiences and rewrote and modified the instructions and forms several times.


“Your Map is Your Guide” was one idea for training enumerators how to understand and use the maps they would receive as a part of their enumeration district portfolio of instructions, forms, and maps.  The enumerator was required to actively use the Enumeration District map by annotating it with the dwelling number of each house in order of visitation, as well as by making corrections, such as new roads and houses.  These markings would show the local Crew Leader that the enumerator had done a complete job of enumeration.


Thus, “Your Map” explained basic concepts of map reading, principles behind the drawing of Enumeration District boundaries, how to use the map to ensure a complete enumeration, and directions for marking the map.  This information included:


  • The U.S. would be divided into about 180,000 Enumeration Districts for the census.
  • Enumeration District boundaries follow visible features (rivers, roads, railroads, etc.) or invisible features (political boundary lines).
  • How to read the “legend” of a map that shows types of buildings or roads.
  • How to read the “scale” on a map that indicates distances.
  • How Enumeration Districts were numbered.
  • How to understand the written description of the Enumeration District.
  • How to mark the map with the serial numbers of the houses in the order in which they were enumerated.
  • How to make corrections for new or nonexistent roads, houses, and other important features.
  • How to determine the “block number” for dwellings in cities.
  • Orange Enumeration District (ED) lines marked on a road (railroad tracks, river, and so forth) meant that the ED boundary was in the middle of the road (railroad tracks, river, and so forth), so that one side of that roadway or waterway was in one ED and the other side was in the other ED.


Let’s take a look at a few of the fun and informative illustrations in this guide.  Perhaps it is a “lost” skill in the electronic era, but let's begin with instructions on determining the distance between two points on a map using the scale (click on the image to see it in a larger size):


This page shows the written description of an Enumeration District and its map:


The centerline or middle of roads, railroads, and waterways often formed the boundary of an Enumeration District:


The enumerator should consult his or her Crew Leader for help with complicated Enumeration District boundaries:


In urban areas, the enumerator should go around each block clockwise:


The enumerator’s properly filled out map - indicating houses in the order of visitation - will help him or her call back at houses where no one was at home:


The map doesn’t show there’s a house down this lane, driveway, or road, but the smart and thorough enumerator will go take a look anyway.  There might be a house!


And finally, ALWAYS have your map since it will save time and steps!