The 1960 census began on April 1, 1960, in accordance with the requirements of an act of August 31, 1954 (amended August 1957), which codified Title 13 of the United States Code. By mid-April, 85 percent of the population of the United States had been enumerated with the count up to 98 percent by the end of the month. Several notable changes were made in the procedures for taking and tabulating the census. These changes were: 1) the greater use of sampling, 2) the development of procedures enabling most householders an opportunity to consult other members and available records when completing the questionnaire for their families, and 3) the use of electronic equipment for nearly all data processing work. ¹

Sampling. In the 1960 census, a 25-percent sample was used. The greater use of sampling meant that the totals for some of the smaller areas were subject to a moderate amount of sampling variation, the usefulness of the statistics was not significantly impaired. Using a 25-percent sample of households eliminated nearly 75 percent of the processing expenses otherwise required for the items in the sample.

Enumeration procedures. The 1960 enumeration was divided into two stages—the first concentrating on quick coverage of the population and the collection of a few items for every person and dwelling unit, and the second devoted to the collection of the more detailed economic and social information required for sample households and dwelling units. Both stages used questionnaires left at the residence to be filled out by one or more members of the family.

The enumeration began prior to April 1, 1960,when an advance census form was delivered by the U.S. Postal Service to each household. The time between delivery of the form and the arrival of an enumerator to collect the household’s information allowed the household to assemble information needed to respond to the census inquiries.

Shortly after April 1, 1960, the second stage of the enumeration began. Enumerators made their rounds to collect the census data and left an additional form—containing the sample inquiries—at every fourth house visited. Households receiving the sample form were asked to complete the form and mail it to their local census office in the postage-paid envelope provided by the enumerator. When these mailed questionnaires were received at the census office, Census Bureau personnel checked the sample forms for accuracy and conducted telephone or personal inquiries to complete unanswered inquiries when necessary.

This two-stage enumeration was believed to be advantageous in that, in the past, enumerators were given only brief special training and were burdened with more instructions and work than they could effectively manage. By creating a two-stage enumeration the field work and training were reduced. Approximately one-third of the enumerator work force was retained for work in the second stage—receiving additional training that focused solely upon the content of the sample questions.

In specified areas (about 15-percent of the total population, characterized as living in areas of low population density and/or having inferior road networks), the two staged enumeration was combined, so that the enumerator collected and recorded sample data in the same interview in which the 100-percent inquiries were recorded.

¹ A. Ross Eckler, “Plans for the 18 th Decennial Census,” presented at the annual meeting of the Rural Sociological Society, Cornell University, August 27, 1959. Pp.3-6. Morris H. Hansen, “Procedures for the 1960 Census of Population and Housing,” presented at the annual meeting of the American Statistical Association, Chicago, Il, December 1958.