A contract for difference (or CFD) is a contract between two parties, buyer and seller, stipulating that the seller will pay to the buyer the difference between the current value of an asset and its value at contract time. (If the difference is negative, then the buyer pays instead to the seller.) For example, when applied to equities, such a contract is an equity derivative that allows investors to speculate on share price movements, without the need for ownership of the underlying shares.

The USD Index is a barometer of the general assessment of the US Dollar relative to a basket of foreign currencies, in a similar way that the Dow Jones Industrial Average is a picture of the US stock market.  It is a leading benchmark for the international value of the US dollar and the world’s most widely traded currency index.   Currently the index is calculated by factoring in the exchange rates of six of the major world currencies.