As a final note, the historically narrow spread between high yield bonds and Triple-B corporates does not mean that the high yield asset class is materially overvalued.

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First-class existing buildings are priced to yield only around 5% to an all-cash buyer, says research firm Green Street Advisors. (The return they talk about is rent minus the costs of operating and maintaining the building and leasing any empty space.) But a skillfully developed new property can bag an annual cash return of up to 10% of its construction costs.

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Yet, high yield issuers are doing pretty good as an investment class.

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Brian Watson : Yeah, you know the yield is really a byproduct of the way the asset class has developed.

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