Trade-Weighted Dollar

A trade-weighted dollar is a measurement of the foreign exchange value of the U.S. dollar compared against certain foreign currencies. Trade-weighted dollars give importance - or weight - to currencies most widely used in international trade, over comparing the value of the U.S. dollar to all foreign currencies. Since the currencies are weighted differently, changes in each currency will have a unique effect on the trade-weighted dollar and corresponding indexes.

The trade-weighted dollar is used to determine the U.S. dollar purchasing value, and to summarize the effects of dollar appreciation and depreciation against foreign currencies. When the value of the dollar increases, imports to the U.S. become less expensive while exports to other countries become more expensive.

Two primary measures of the trade-weighted dollar are used. The first is the U.S. Dollar Index, created in 1973. It is calculated using six major world currencies: the euro, Japanese yen, Canadian dollar, British pound, Swedish krona and Swiss franc. The euro makes up more than 57 percent of the index weighting. 

The second is the Trade Weighted U.S. Dollar Index, sometimes called the Broad Index. This index was introduced by the U.S. Federal Reserve Board in 1998 in response to the implementation of the euro (which replaced many of the foreign currencies that were previously used in the earlier index) and to more accurately reflect current U.S. trade patterns. The Federal Reserve selected 26 currencies to use in the broad index, anticipating the adoption of the euro by eleven countries of the European Union (EU). When the broad index was introduced, U.S. trade with the 26 represented economies accounted for over 90% of the total U.S. imports and exports.

During the financial crisis, both measures of the trade-weighted dollar rose sharply during the Great Recession as investors flocked to the U.S. dollar, which is considered a safe haven currency.