Short term government bonds pay at least 7.25%, sometimes more depending on the maturity date.

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Once a municipal bond is refinanced, (prerefunded) the issuer uses the proceeds of the new issue and purchases US Treasury securities (collateral) that are used to pay the interest and principal on the original, more expensive debt until maturity or the call date, whichever the escrow agreement states.

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In October, the company restructured the securities so the original maturity date was extended, with half the principal balance being due on Feb. 15, and the rest on March 13.

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The Fed Publishes maturity date data on its treasury holdings once per week.

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