For survival, it is useful to estimate the level of the risks they are supposed to manage at close to, but not quite, zero.

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Given that the venues are designed to provide as much capacity as possible for those events that are extremely popular, then it could be that a less popular event will not sell out even if prices are close to zero.

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It is not difficult to work out that, from the Fed's point of view, this brings them dangerously close to zero.

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There is high unemployment and ordinary savers are getting close to zero returns, while many young people and not so young people are crushed by non-dischargeable student debt.

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And it is not just the U.S. Global real broad money growth is close to zero.

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They say that if Japan's economy does not start showing signs of recovery, and with interest rates in the country close to near zero, it may see a rise in "carry-trades".

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