While unilateral intervention is unlikely to change long term trends, it is used to deter excessive speculation and attempt to reduce volatility in favor of more 'orderly' movement.

虽然单方面干预不大可能改变长期走势，但往往会威慑过度投机行为及降低波动，使走势更加“有序化”。

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This is a fairly common approach that entails buying and selling different sorts of options to reduce volatility.

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Holding periods theoretically reduce volatility and destabilizing speculation and encourage long-term investing.

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It is not possible to impose an FTT on foreign exchange transactions in the EU. An FTT will not reduce volatility, it will increase it.

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