The above chart gives a histocial view of the major currencies dollar index. The Federal Reserve defines the major currencies index as “a weighted average of the foreign exchange values of the U.S. dollar against a subset of currencies in the broad index that circulate widely outside the country of issue.” Basically, it shows the strength of the U.S. dollar against a basket of major currencies (lower index numbers indicate a weaker dollar).
Data source:
U.S. Federal Reserve report H.10 Foreign Exchange Rates (summary measures)
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