These data files are developed each year to support creation of the Private Pension Plan Bulletins. For the 2000-2009 Pension Research Files, they include Form 5500 filings from all private pension plans having 100 or more participants and a 5 percent sample of smaller private pension plans. Beginning with the 2010 Pension Research File, sampling is no longer necessary due to improved data collection methods. The private pension plan research files correct many statistically important logical and arithmetic data inconsistencies that remain after completion of EFAST processing. The downloadable zipped pension research files below include SAS datasets suitable for use on a Windows operating system, sample SAS tabulation programs, a SAS formats program, and documentation. The Pension Research File User Guides provide information on the construction of, structure of, and variables included on, the Form 5500 Private Pension Plan Research File. Information on how to request the pension research files in formats other than SAS data sets or for non-Windows operating systems can be obtained by contacting EBSA's Office of Outreach, Education and Assistance.