1. The American Community Survey (ACS) Lisa Neidert NPC Workshop: Analyzing Poverty and Socioeconomic Trends Using the American Community Survey June 23 – June 27, 2008

2. What is the ACS?  A large, continuous survey Produces single and multiyear estimates of the characteristics of the population and housing Produces information for small areas including tracts, block groups and population subgroups Key component of the decennial census program

3. Origins of the ACS  More timely data  Operational reasons Steadier funding Year-round Interviewing  Skilled interviewers instead of temps  Strengthen Decennial Census Improved census geography  Updated address files

4. More timely data  Mariel Boat Lift  Natural disasters

5. More timely data...  Communities  Populations

6. ACS Implementation  Demonstration Period 1996-2004

7. ACS Implementation  Full implementation: 2005* Every county nationwide Products released in 2006 Annual updated data products released every year thereafter * Did not include group quarters in 2005

8. Data Release Timetable

9. Sample Specifics  3,000,000 addresses 250,000 a month

10. Interpreting ACS data  Universe and Residence Rules  Time periods  Reference periods  Comparison Guidelines http://www.census.gov/acs/www/UseData/ compACS.htm

11. ACS Universe  Total resident population of the United States  Group Quarters population added to the sample in 2006  Example Ann Arbor, MI, 2006: 112,371 Ann Arbor, MI, 2005: 98,743 Ann Arbor, MI, 2000: 114,024

12. Residence Rules  Resident of the housing unit if: Lives there year round Lives there more than 2 months but not year round Is living there now with no other place to live Is away now for 2 months or less  Not a resident of the housing unit if: Lives there 2 months or less with another residence Is away now for more than 2 months

13. Reference Periods  ACS uses the interview data as the single reference point, or as the end of a reference period, for all data collection Interviewed in October 2006  Earnings reference period: October 1, 2005 – September 30, 2006

14. Data Products: Annual  Tabular Detailed Subject Geographic Comparison Ranking  Microdata 1 percent  ~1,300,000 housing records  ~3,000,000 person records

15. Data Products: Multi-year  3-year: 2005 - 2007 Release dates: August 2008+  Multiyear Estimates Study 5-year; 3-year; 1-year For test communities only  34 counties http://www.census.gov/acs/www/AdvMeth/Multi_Year_Estim ates/overview.html#noteforusers

16. Microdata vs Tabular  Census Bureau website emphasizes tabular data via American FactFinder FTP is interface to microdata  Exceptions  Workshop Micro (65%) Tabular (35%)