The markets that do the sort of high volume, low margin trades that would be affected by an FTT are the foreign exchange (FX), futures, options and stock markets (with special reference to high frequency trading of the often demonised computer algorithm type).

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After speaking with many traders with color-vision deficiencies, designers of DJ FX Trader, a foreign exchange tool offered by Dow Jones, the publisher of The Wall Street Journal, say they made a point of using icons to supplement color.

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The G7 announced they will cooperate as appropriate in the foreign exchange markets and combat excessive FX volatility.

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