The U.S. Dollar Index® represents the value of the US Dollar in terms of a basket of six major foreign currencies. It is a weighted geometric mean of the dollar’s value compared only with:
- Euro (EUR) = 57.6% weight,
- Japanese Yen (JPY) = 13.6% weight,
- UK Pound (GBP) = 11.9% weight,
- Canadian Dollar (CAD) = 9.1% weight,
- Swedish Krona (SEK) = 4.2% weight, and
- Swiss Franc (CHF) = 3.6% weight.
USDX goes up when the US dollar gains “strength” (value) when compared to other currencies.
USDX started in March 1973, soon after the dismantling of the Bretton Woods system. At its start, the value of the US Dollar Index was 100.000. It has since traded as high as 148.1244 in February 1985, and as low as 70.698 on March 16, 2008, the lowest since its inception in 1973.
The makeup of the “basket” has been altered only once, when several European currencies were subsumed by the Euro at the start of 1999.
USDX is updated whenever US Dollar markets are open, which is from Sunday evening New York time (early Monday morning Asia time) for 24 hours a day to late Friday afternoon New York time.
It is an exchange traded (FINEX) index and has become a standard used worldwide.