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RAT-STATS is a package of statistical software tools designed to assist the user in selecting random samples and evaluating the audit results. The goal behind RAT-STATS was to develop valuable analytical tools that could be easily used by auditors.

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Extract zip files to a folder on your hard drive. Run SetupRS2007v2.exe and follow the installation instructions.


RAT-STATS is the primary statistical audit tool used by the Office of Audit Services. Developed by the Regional Advanced Techniques Staff (RATS) in San Francisco, it has been used by the Office of Inspector General since the early 1970s. With the arrival of microcomputers, there was opportunity to move the statistical software from the mainframe timeshare systems.

In September 1987, the first microcomputer version of RAT-STATS was developed to run on IBM compatible computers using Microsoft's Disk Operating System (MS-DOS).

In September 2001, Windows RAT-STATS Version 1, which includes the most frequently used programs from the DOS version, was completed. Windows RAT-STATS 2007 includes all programs from the DOS version.