American Community Survey (ACS)

The American Community Survey (ACS) is a nationwide survey designed to provide communities a fresh look at how they are changing. It is a critical element in the Census Bureau’s decennial census program. The ACS collects information such as age, race, income, commute time to work, home value, veteran status, and other important data. As with the 2010 decennial census, information about individuals remains confidential.

ACS is published every year instead of every ten years. Collecting data every year provides more up-to-date information throughout the decade about the U.S. population at the local community level. About 3.5 million housing unit addresses are selected annually, across every county in the nation.

How Emsi Incorporates ACS

Emsi’s Self-Employed Class of Worker includes all people who consider self-employment a significant part of their income and/or taking a significant part of their time. Emsi largely bases job counts, hourly earnings, and projections for these unincorporated self-employed jobs on responses to the American Community Survey (with additional input from other sources).

Emsi’s Extended Proprietors Class of Worker represents jobs that generate miscellaneous labor income, such as very small self-employment income and partnerships with many partners having limited involvement. Emsi derives job counts and hourly earnings for Extended Proprietors from differences between ACS and other proprietor counts, the latter of which are based on tax returns and other data compiled by the Bureau of Economic Analysis as well as local personal income reports.

Emsi also uses ACS to construct industry and occupation diversity data, which provides demographic breakouts of the workers in a given industry or occupation. We also publish many of the social and economic indicators that the ACS gathers and distributes through their various APIs.

Strengths of ACS

• ACS covers a wide variety of data, providing information on national demographic, social, economic, and housing characteristics.
• Responding to the Survey is mandatory for the housing units that are selected, so participation is strong.

Weaknesses of ACS

• ACS is a survey, meaning it is subject to various forms of measurement error such as sampling error, misclassification (industry/occupation) error, and even incomplete or misleading responses.
• Because it is designed to ensure good geographic coverage and does not target individuals, the Census Bureau selects only a small, random sample of about 295,000 addresses (of more than 180 million people) to be included in ACS each month.
• The full implementation of ACS began in 2005, so historical data is limited.

For more information visit the ACS website.