The US Federal Reserve has a system to control the amount of currency in circulation.

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There is only one possible outcome from leaving the unwanted currency in circulation.

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That is what it is now doing: Japan's monetary base (currency in circulation and banks' reserves at the Bank of Japan) grew by 23% in the year to January.

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Our earlier use of this policy approach had little effect on the amount of currency in circulation or on other broad measures of the money supply, such as bank deposits.

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Under a currency board arrangement, the central bank guarantees the redemption of all notes in circulation at a set exchange rate to the dollar or another foreign currency or basket of currencies.

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Like swaps on interest rates and foreign currency, credit swaps outstanding dwarf the underlying bonds in circulation.

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Our central bank has not fully grasped that the dollar is now an international currency, with more than 60% of that now in circulation being used as transaction money outside our borders.

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The value of euro banknotes in circulation and the market for euro-denominated securities already rival the dollar, a long-established currency backed by a single nation-state.

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