There are 10 million families with homes underwater, their mortgages exceeding today's clearing prices.

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Some clients of the exchanges say their merger will reduce competition and threaten to raise prices on trade clearing.

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If labor and other markets are allowed to function without government intervention, there will be a tendency toward market-clearing prices, including relative wage rates and interest rates that reflect time preferences and the productivity of capital.

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The same is true of fixing prices above the market clearing price.

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In that case, if exporters are struggling to sell their products, the more apparent near-term problem is that their own high prices are making inventory clearing a distant object.

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Along with a better-than-expected macro environment in August, surplus inflows to the loan market lifted secondary prices and pressured new-issue clearing yields lower.

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Or, if you prefer, the futility of trying to fix prices at any point other than their market clearing price.

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