An accounting estimate of the number of years it is likely for an asset to remain in service for the purpose of cost-effective revenue generation. The Internal Revenue Service (IRS) employs Useful Life for various purposes applicable to Tax-Exempt Bonds.

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Changes to the operations and accounting of funds under the supervision of the U.S. Department of Treasury that allow the federal government to continue paying bills and most operations after the U.S. has reached or neared its debt limit.