The initial price thinking for the 2021 maturity was a 5% coupon to yield 3.20%.

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Tenet Healthcare and Denbury Resources this week became the latest high-yield issuers to capture coupon rates that were below the 5% threshold, and in doing so they logged some new records.

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The offering coupon on the bond, which is the yield the government agreed to pay on the debt when it registered the issue with the market, was 4.875% before high demand brought the yield to its lowest ever.

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When the Gap launched its 10-year bond with a 5.95% coupon on April 8, it was prices to yield about 238 basis points more than the 10-year treasury yield.

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That's a shame for investors, because around 90% of the market's long-term return can be linked directly to dividends--the basic yield and then the growth over time of that coupon.

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The interest on municipal bonds is exempt from income tax on the federal and sometimes state levels, giving them a higher after-tax yield than a corporate or Treasury with the same coupon and maturity.

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On the 10 year auction launched on August 12, Smith bought at par for a yield of 2.84% and made 7 points plus the coupon for a return of almost 10%.

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High yield bonds, plus 1 percent, seem on track to earn their coupon (6 percent) but little more.

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