Status:Closed    Asked:Jun 02, 2017 - 01:30 PM

Why can't I match the American Factfinder numbers?

I downloaded an IPUMS data set about commute type for various metro regions, however, for some reason I can't seem to match the data on the American Factfinder website, which I was doing just to confirm I understand things correctly. When I look at total workers over 16 years of age, for the Raleigh metro (39580) I get either 656,611 from the ACS 1 year or 616,341 from the ACS 5-year. The American Factfinder site says that it is using the ACS 5-year. Since I'm looking at commute type breakdown, I also checked percentages and still couldn't match the American Factfinder data perfectly. When I look at driving alone, I get 80.2% (in Raleigh metro) from the ACS 1-year, 80.7% from the ACS 5-year, and using the numbers on the American Factfinder site, I get 80.3%, so the ACS 5-year is a larger difference even though it is what the Factfinder says it is using.

So where does the difference here come from? Which data set should I be using?

Thanks. - Josh

Do you have the same question? Follow this Question

Staff Answer




Estimates derived from the ACS public use microdata are expected to differ from the summary tables available through American FactFinder. This is because the summary tables use the full ACS samples while the public use microdata files include a subset of the sample (about two thirds). The microdata sample is then re-weighted to match the total population figures. While we do expect estimates to differ, they should generally still fall within the published margins of error.

I hope this helps!



Jun 05, 2017 - 09:38 AM

Report it


2011 ACS 5 Year Sample -- Connecting Aggregate County Level Info to Microdata
Why is the American FactFinder have considerable higher poverty rates than AC...
number of region to region movers calculated using IPUMS ACS 2015 doesnot mat...
Should OCC2010 (ACS IPUMS) match or approach the values in ACS occupation in ...
Login   |   Register

Recently Active Members

View More »

Share |