<Tr> <Th_colspan="2"> Footnotes </Th> </Tr> <Tr> <Td_colspan="2"> Measurable benefits of GAO work total $49.9 billion, a return of $87 for every dollar invested; at the end of FY 2010, over 80% of the GAO recommendations made in FY 2006 had been implemented . </Td> </Tr> <P> The Government Accountability Office (GAO) is a legislative branch government agency that provides auditing, evaluation, and investigative services for the United States Congress . It is the supreme audit institution of the federal government of the United States . </P> <P> The GAO was established as the General Accounting Office by the Budget and Accounting Act of 1921 . The act required the head of the GAO to "investigate, at the seat of government or elsewhere, all matters relating to the receipt, disbursement, and application of public funds, and shall make to the President...and to Congress...reports (and) recommendations looking to greater economy or efficiency in public expenditures". According to the GAO's current mission statement, the agency exists to support the Congress in meeting its constitutional responsibilities and to help improve the performance and ensure the accountability of the federal government for the benefit of the American people . </P>

What is the purpose of the general accounting office (gao)
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