U.S. Census Bureau Releases 2011-2015 American Community Survey 5-Year PUMS Files and Variance Replicate Estimate Tables

2011-2015 ACS 5-Year PUMS Files

We are pleased to announce the release of the 2011-2015 American Community Survey (ACS) 5-year Public Use Microdata Sample (PUMS) files

The ACS 5-year PUMS files show the full range of population and housing unit responses collected on individual ACS questionnaires for a subsample of ACS housing units and group quarters persons (approximately five percent of the United States population).

PUMS files allow data users to conduct a custom analysis, though the files also tend to be more complicated to use. Working with PUMS data generally involves downloading large datasets onto a local computer and analyzing them using statistical software such as R, SPSS, Stata, or SAS.

PUMS data can be accessed via the Census Bureau's FTP site, American FactFinder, or via the DataFerrett tool. (This tool is particularly useful for researchers who need a quick statistic or do not have access to statistical software.)

For more information, explore the new 2011-2015 ACS 5-year PUMS Technical Documentation:

  • PUMS ReadMe: Information about geography and variable changes, as well as guidance for novice users.
  • Code Lists: This document contains the detailed codes for variables that contain a large number of coded responses, such as ancestry and occupation.
  • Subjects in the PUMS: A list of broad topics included in each of the housing and population record files.  
  • Data Dictionary: Full listing of all variables (and values) included in each of the housing and population record files.
  • Accuracy of the PUMS: Explanation of the sample design, estimation methodology, and accuracy of the data.
  • PUMS Estimates for User Verification: If users have doubts about whether they are correctly computing estimates, they can attempt to reproduce these estimates (using the replicate weight method).


2011-2015 Variance Replicate Estimate Tables



We are pleased to announce the release of the 2011-2015 ACS Variance Replicate Estimate Tables. These tables include estimates, margins of error (MOEs), and 80 variance replicate estimates for selected ACS 5-year Detailed Tables. With the replicate estimates, advanced users can calculate MOEs when collapsing data within a table or across geographies. This method provides a more accurate MOE than available approximation formulas.

To access these estimates, visit the Variance Replicate Estimates page or through the Census Bureau's FTP site.

For more information, visit the Variance Replicate Estimate Tables documentation page:

  • 2011-2015 Variance Replicate Estimate Tables Documentation: Learn how to calculate margins of error for aggregated estimates, percentages, and ratios through these instructions with worked examples.
  • Variance Replicate Estimate Table and Geography List: Learn which tables and types of geographic areas have variance replicate estimates.
  • Table Shells: View the layout of tables without the estimates or margins of error filled in.


The ACS provides reliable statistics that are used to make informed decisions about the future. These statistics are required by all levels of government to manage or evaluate a wide range of programs, but are also useful for research, business, education, journalism, and advocacy. If you have questions about this survey, please call our Customer Services Center on 1 (800) 923-8282.  


Thank you,

American Community Survey Office

U.S. Census Bureau

  • Has anyone else encountered problems accessing the 2011-2015 U.S. person PUMs file? I have been trying unsuccessfully to open csv_pus.zip, and I think the zip file may be damaged. When I download and open the folder, one of the four CSV files (ss15pusa.csv)  shows up as being HUGE. It's listed as being 800 petrabytes in the size column in the Windows folder view. As a result, I cannot copy or unzip the file due to hard drive limitations. Yet when I right-click on the file and view the properties, it says it's only 1,013,506 KB uncompressed. The other three files seem fine. I have tried downloading the zip file from both Factfinder and the FTP site without success. Census folks, is it possible to check on this and upload a new file if necessary? Thanks!

  • In reply to Alicia Mazzara:

    Hello Alicia,
    As I was trying to replicate the error, I was able to successfully download and extract the ss15pusa.csv file from the Zip File. Here is what I did:

    1. Downloaded 2011-2015 5-Year PUMS Population zipfile from the American Factfinder site (2.4 GB)
    2. Opened the file with Winzip. The file ss15pusa.csv inside is 726 MB.
    3. Extract the file, which now uncompressed is 4.29 GB.

    Did you try again? Are we doing anything different?

    Please let us know.

  • In reply to Javier:

    Hi Javier,
    I think the problem must be with my computer, as I'm doing the same steps. Thank you for checking!
  • Hi Alicia,

    I hope you've gotten this to work in the last few months...but for anyone else who is having this same problem, I downloaded 7Zip, and then the enormous file was no longer enormous, and I was able to download it without a problem.