American Community Survey - Implementation

Implementation

The ACS has an initial sample of approximately 3 million housing unit addresses and group quarters in the United States, with sample selected from all counties and county-equivalents, American Indian and Alaska Native area, and Hawaiian Homeland, and in Puerto Rico annually. Data are collected primarily by mail, with follow-ups by telephone and personal visit. Approximately one third of those who do not respond to the survey by mail or telephone are randomly selected for in-person interviews, and the final response rate for that group was 98 percent in 2009. Because approximately two-thirds of mail/telephone nonrespondents are not selected for in-person follow-up interviews, the ACS only includes approximately 2 million final interviews per year. In 2009, completed ACS interviews represented 66.2 percent of the housing units initially selected for inclusion in the sample.

The Department of Commerce has stated that those who receive a survey form are legally obligated to answer all the questions as accurately as possible. Those who decline to complete the survey may receive follow-up phone calls and/or visits to their homes from Census Bureau personnel. Section 221 of Title 13 U.S.C., makes it a misdemeanor to refuse or willfully neglect to complete the questionnaire or answer questions posed by census takers and imposes a fine of not more than $100. This fine was changed by the Sentencing Reform Act of 1984 from $100 to not more than $5,000. The Census Bureau prefers to gain cooperation by convincing respondents of the importance of participation. To date, no person has ever been charged with a crime for refusing to answer the ACS. The Department of Commerce states that it is "not an enforcement agency".

The processed information provides yearly estimates for all states, as well as all cities, counties, metropolitan areas, and population groups of 65,000 people or more. For smaller areas, it is necessary to combine multiple survey years to obtain reliable estimates: three survey years in areas with 20,000 to 65,000 people, and five survey years in areas with fewer than 20,000 people. The quality of these samples was originally intended to match that of the decennial census long form, but because the sample size of the ACS is smaller than originally expected, ACS estimates are less precise than the comparable estimates from Census 2000 and prior decennial census years.

Survey methods:

• Mail: Self-enumeration
• Computer Assisted Telephone Interviewing (CATI), approximately 3 weeks after the mailout
• Computer Assisted Personal Interviewing (CAPI) by Census Bureau field representatives.