Groupon faces slowing consumer interest in its online coupons, and has restated its financial results more than once.

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Investors gravitated toward longer maturity bonds in an effort to secure higher coupons since older investors often rely on interest payments to sustain their income.

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Moreover, as bond coupons fall, their duration, or their sensitivity to interest rates swings, goes up.

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Also, coupons on Treasurys are exempt from state income tax, while interest on corporate bonds and Ginnie Maes is not.

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With interest rates still low, companies are refinancing to get longer maturities and lower coupons.

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My suggestion to him was that in the current environment he should eliminate all the high-coupon debt and replace it with 5% or 6% coupons carrying equity participation--give up some equity in return for much lower interest rates.

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Long bonds usually have higher coupons than short ones, as investors demand a premium for exposure to the risk of interest-rate rises and inflation.

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With interest rates at paltry levels and seemingly destined to rise, bond owners confront the ugly possibility that any coupons they receive will be wiped out by capital losses.

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