What’s the difference between the 1930 and 1940 United States censuses?
While the question may sound like the opening to a joke, it isn't a joke at all! Basically every United States census has differed from previous censuses, an interesting challenge for people doing family history. While the 1930 and 1940 U.S. census questions have minor differences, such as using the word “home” instead of “abode,” the more important changes were all the new questions added after the events of the 1930s.
Searching 1940 census records will provide you with insight into the life events of American citizens who had just experienced the Great Depression, Dust Bowl, and beginning events of World War II. And while you won’t find out if your ancestor had a radio set (a question in the 1930 census), the 1940 census might reveal your family member’s income level and occupation.
Types of Questions in the 1940 United States Census
The 1940 census had 34 questions on the short form for the general public and 16 supplemental questions to be asked of 5 percent of the population. Written by the United States government to gain insight on how to guide public policy, the 1940 census questions are very descriptive and focus noticeably on migration, education, and work.
The 1940 U.S. census form (including the supplemental section) had the following types of questions:
- 6 home and household questions
- 6 personal description questions
- 2 education questions
- 3 place of birth questions
- 1 citizenship question (for foreign-born citizens)
- 1 mother tongue question
- 4 questions on residence in 1935 (for tracking internal migration)
- 3 Social Security questions
- 4 marriage and natural-born children questions
- 3 veteran status questions
- 17 employment and occupation questions
That is a lot of questions! With all that information available on a 1940 census record, the record can be hard to read (especially since the census takers took notes by hand). Here's a guide to help you find the information you’re looking for: “Questions Asked on the 1940 Census.”
New Questions on the 1940 U.S. Census Form
The bulk of the new questions on the 1940 census form are employment and occupation questions, but questions were also added about migration and education.
General Employment Questions
The 1940 census added 11 new questions on employment, including some about “emergency government work.” If your ancestors participated in this type of work, they may have been hired by one of President Franklin D. Roosevelt’s “New Deal” organizations, which sponsored federally-funded jobs for farmers, artists, other laborers, and even students.
Income—A Controversial Question
Fun fact, the very last questions asked on the main section of a 1940 census form were income questions, and this placement was very deliberate. This was the first time the government had asked about a person’s income on a federal form, and the Census Bureau anticipated it would be a sensitive topic for many United States residents.
As noted by Edwin D. Goldfield, a retired Census Bureau worker, “That question was put at the end of the interview because if the enumerator got kicked out of a household when [the] question was asked, the interviewer would have already obtained the answers to the previous questions. It caused a great uproar in the country.”
To encourage more citizens to answer the income question honestly, census takers were instructed to just write +$5,000 for larger incomes.
Internal Migration and Immigration
You may wonder why the 1940 census asked for each person’s residence on April 1, 1935—five years before the census was taken. This question gave the government insight about internal migration in the United States.Your family members’ answers might help you learn if they moved just before this census, whether they lived on a farm, and whether they lived in a large town or city.
Their immigration information might also be found on the 1940 census, and this census is the first one to indicate whether they might have been an American citizen born abroad.
Among the 2 education questions on the 1940 census, only one was new. If you want to know the highest grade of school your family members completed, their 1940 census records may clue you in.
The Newfangled Supplemental Section
The 1940 census was also the first to include a sample survey. Statistical sampling was a fairly new at the time, and the Census Bureau took the lead in following newly-tested survey procedures. Census takers were instructed to ask additional survey questions to people whose names landed in rows 14 and 29 on the general census, no matter if it was a man, woman, or child. These survey questions can help you learn even more details about your ancestor’s life story.This supplemental section is where you will find veteran information in 1940 census records, including which wars your ancestors may have served in or if your family member was the wife, widow, or child of a veteran.
Whether your family members had a Social Security number is also included in the supplemental section. (If so, try looking them up in the U.S. Social Security Death Index!) Alongside the retirement information, you can also see what your family members described as their “usual occupation,” which, just following the Great Depression, was different for many people than their current employment. Just following the Great Depression.
Lastly, about female ancestors who answered these additional questions, you might learn if they had been married more than once, what their age was at the time of their first marriage, and how many naturally-born children they had (not including stillbirths).
Find Your Own Family Members’ 1940 Census Records
Whether you have living memory of your 1940 ancestors or not, you might learn some unique information about them in the 1940 census, or the information may help you build branches of your family tree!
Learn More about the 1940 U.S. Census
How did life and events in the 1930s impact the census? And what can you learn about your ancestors’ lives?
Learn about the 1940 U.S. census and how it can provide important clues about your family history.