"Census data" most often is associated in the public mind with population. The U.S. census enters America's consciousness every ten years, usually in the form of a long, detailed mail-in questionnaire, quickly forgotten when it's mailed back. It would surprise many to learn that census data are used in a multitude of different ways. While the decennial population count is by far the biggest census that the U.S. Bureau of the Census undertakes, the Bureau also does thousands of different censuses, some annually, others monthly, while the U.S. Economic Census comes out every five years. The data results of all the censuses are awaited eagerly by members of Congress, federal and state agencies, and businesses throughout the United States.


As to the biggest and oldest census, the population count, there is almost no resemblance between the census of today and the first official one tabulated over two hundred years ago. The Articles of Confederation made no provision for a national census. The issue only arose when a federal constitution was debated in 1789. When delegates to the constitutional convention finally agreed to accept population as the principle of representation in the House, it became a problem to decide whom to include in the population. Delegates from southern states wanted slaves to be counted equally with white men and women, while northerners, fearing overrepresentation of southern whites in Congress, insisted that three slaves equaled only one white person. Native Americans would not be included at all. Finally, the Constitution mandated a national population census every ten years.

In 1880, Congress decided to do something about streamlining the census process, hence mandating the establishment of a separate Census Office in the U.S. Department of the Interior, which would hire professionals to do the census. Special punch card tabulating machines were introduced, while women were hired for the first time as enumerators. In 1904, the Census Bureau was made a permanent part of the newly created U.S. Department of Commerce.

A new and rather daring departure from the traditional human census counter occurred in 1910, when the Census Bureau decided to introduce the census questionnaire by mail. Either because the public was insufficiently educated on the importance of the census or because few people had private telephones for follow-up reminders, most discarded the census form with its prying questions, necessitating the return of the census counter.

Conceived by bureau mathematicians in 1943, the sample survey queried only a small percentage of the population to produce results reflective of the population at large. The sample survey opened the door for a multitude of different, and more detailed, surveys in the future, and is still used today.

To tabulate all of this data would have been a gargantuan task for a human enumerator. Computers were first used to handle the 1950 census, which at the time was the biggest population survey ever conducted.



Aside from the decennial census, probably the most important demographic study by the Census Bureau is its monthly Current Population Survey (CPS), which is conducted in conjunction with the Labor Department's Bureau of Labor Statistics. This survey tabulates the U.S. population by age, sex, ethnicity, employment status, income, immigration, occupation, education, and other characteristics. The CPS provides the basis for a monthly estimate of the current U.S. population count. Other demographic information the bureau collects include data on housing and homeownership, health insurance, poverty, and disabilities.

Personal information from surveys and censuses is generally not publicly disclosed for commercial or private (such as genealogical) use. There is a 72-year confidentiality period on all personal-level census data, meaning that, for instance, in 2002 personal data from the 1930 census will be published. However, even then this information is released directly to libraries and archives rather than to individual researchers.


Business, industry, and commerce are documented either monthly, annually, biannually, or quinquennially in the form of census surveys and polls, averaging two thousand a year. Some of the census data are published in the form of one or two page reports; others are compiled annually into the thousand pages of the Statistical Abstract of the United States. Much historical economic—as well as demographic—information is available on CD-ROM and on the Census Bureau's web site.

The Economic Census, which is conducted in years ending in two and seven and released approximately three years later, is the bureau's largest economic data product. It includes detailed data on all areas of the U.S. economy as grouped by Standard Industrial Classification, and as of the 1997 edition, North American Industry Classification System categories. The data includes the number of businesses in each industry, industry revenue figures, and geographic breakdown of industry firms.

In addition to the major Economic Census, the bureau publishes many surveys used by economists and business analysts. A few of the most important include:

Virtually every business could benefit from using census data. Private entrepreneurs, from barbershop owners to the self-employed, can turn to the Census Bureau's popular publication, Taking Care of Business: A Guide to Census Bureau Data for Small Businesses. For example, a restaurant in Los Angeles was able to contact the Census Bureau to find out the number of residents from the Deep South residing in the city, in order to determine how many ham hocks the restaurant should order. For a business catering to an ethnic minority, the census provides the population figure, location, and incomes for that ethnic group, and much more data besides. Certain companies can plot their future marketing strategies more effectively when they discover that the 1990 census indicates that by 2050, America's elderly population—those over 85 years of age—will have increased sixfold. Census data can tell a utility business the percentage of homes that use gas for heating and cooking. Lastly, the Census Bureau cooperates with the U.S. Small Business Administration (SBA) to provide statistics for a range of publications and helps organize seminars and workshops throughout the country.


Approximately 40,000 different federal, state and local government agencies and business entities rely on the diverse data collected by the Census Bureau. The president is mandated to present the decennial census results before Congress by January 1 of the year following the taking of the population census, which is the signal to begin reapportionment of seats in the House. Several months later, on April 1, every state must have received a detailed population count from the Census Bureau to begin reapportionment of its legislature (which also includes county and municipal legislatures). Major cities also are vitally interested in the census data, since the population figures determine the amount of federal aid they receive. Anyone interested in ascertaining the amount of spending by state and local governments can also find this in the census data.



Despite the utility and profit derived from using or marketing census data, there have nearly always been controversies surrounding the Census Bureau and the data it gives out. Because census data are vital in determining the amount of federal aid to cities, and whether or not to expand low income housing and other social programs, the Census Bureau has faced dozens of lawsuits alleging undercounting of minorities. The bureau publicly acknowledges its shortcomings in correctly counting the population in the decennial census. In the 1970 census, for example, the population was underestimated by around 5 million, the vast majority of whom were members of minority groups. Better census methods resulted in the smallest undercount of any census for the 1990 population count. In that census, the Hispanic population was underestimated by only 5.2 percent, African-Americans by 4.8 percent, Native Americans by 5 percent, and Asian and Pacific Islanders by 3.1 percent. Undercounting minorities can have severe consequences for cities that rely on federal grants. It also angers minority groups who feel left out of reapportionment and whose poor are underserved. Businesses also seek accurate minority data for marketing purposes.

The bureau's solution to the undercounting has been to try to implement expanded use of statistical sampling in the decennial census, a proposition that has drawn the ire of political conservatives. While such methodology is widely used and supported by statistics professionals in business and academia—and, in those circles, is believed highly reliable if designed properly—opponents insist that it is open to illegal tampering for political purposes and is even unconstitutional.


Besides the criticisms the Census Bureau has had to face regarding population undercounts, the matter of privacy has continually perplexed census efforts. While the postwar decades have escalated the pressure on the bureau to provide increasingly detailed information, there is resistance to the "prying" nature of census questionnaires on the part of the public, from businesses to private individuals. The well-known fear of illegal immigrants of filling out the census questionnaires is partly the reason for the undercount of the Hispanic population, for which the bureau gets blamed. Since 1929, the bureau has been especially mandated to keep all of its information confidential. Nonetheless, the computerization of government has cast public doubt on the "leakproof' nature of census information.


The public's, as well as government's, demands for more diversified data have been another problem for the Census Bureau. In the 1950s and 1960s, in response to these pressures, census data became ever more detailed, covering smaller and smaller geographic areas. This has enormously expanded the mandate of the Census Bureau from what it was initially called upon to do and has increased sizably the bureau's budget. In the mid-1990s, federal budget cuts reduced Census Bureau funding, as well as that for other statistical agencies, and caused the bureau to scale back some of its data collection and analysis activities. There are indications that even the ten-year population count will change significantly in the 21st century, possibly involving only a sample survey of a small percentage of the population, obviating the need, for instance, to tabulate the more than 100 million household questionnaires that would otherwise be necessary. Some believe that census data and many other surveys may be conducted increasingly by the private sector, especially universities and research firms.


Crispell, Diane. "Drawing the Line." American Demographics, July 1996.

Lavin, Michael R. Understanding the Census: A Guide for Marketers, Planners, Grant Writers, and Other Data Users. Phoenix: Oryx Press, 1996.

U.S. Census Bureau. "About the Census Bureau." Washington, 1998. Available from www.census.gov .

Other articles you might like:

User Contributions:

Comment about this article, ask questions, or add new information about this topic: