American Community Survey (ACS)

The 2014 Design and Methodology Report contains descriptions of the basic design of the American Community Survey and details of the full set of methods and procedures. We have archived the previous version of the report.

The American Community Survey (ACS) is a relatively new survey conducted by the U.S. Census Bureau. It uses a series of monthly samples to produce annually updated estimates for the same small areas (census tracts and block groups) formerly surveyed via the decennial census long-form sample. Initially, five years of samples were required to produce these small-area data. Once the Census Bureau, released its first 5-year estimates in December 2010; new small-area statistics now are produced annually. The Census Bureau also will produce 3-year and 1-year data products for larger geographic areas. The ACS includes people living in both housing units (HUs) and group quarters (GQs). The ACS is conducted throughout the United States and in Puerto Rico, where it is called the Puerto Rico Community Survey (PRCS). For ease of discussion, the term ACS is used here to represent both surveys.

This document describes the basic ACS design and methodology as of the 2013 data collection year. The purpose of this document is to provide data users and other interested individuals with documentation of the methods used in the ACS. Future updates of this report are planned to reflect additional design and methodology changes. This document is organized into 16 chapters. Each chapter includes an overview, followed by detailed documentation, and a list of references.