U.S. Dollar Index®: What It Is and Its History

Six Currencies Used in the U.S. Dollar Index

Currency board
The dollar index shows the dollar's value against a basket of currencies. Photo: Ryan Peirce/Getty Images

Definition: The U.S. dollar index® is measurement of the dollar's value according to a basket of six exchange rates. Over half of the value is the dollar's value measured against the euro. The other five currencies are the Japanese yen, the British pound, the Canadian dollar, the Swedish krona and the Swiss franc. 

The formula is:

USDX = 50.14348112 × EURUSD -0.576 × USDJPY 0.136 × GBPUSD -0.119 × USDCAD 0.091 × USDSEK 0.042 × USDCHF 0.036

The value of each currency is multiplied by its weight. Note that the weight is a positive number when the U.S. dollar is the base currency, and negative when the U.S. dollar is the quote currency. Euros and pounds are the only two where the U.S. dollar is the base currency. That's because they are quoted in terms of dollar. For example, a euro is worth $1.13. The other four are quoted in terms of how many a U.S. dollar will buy. For example, a dollar is worth 109 yen. (Source: "U.S. Dollar Index® Contracts," ICE Futures U.S., June 2015.)


In 1973, the Federal Reserve created the index to keep track of the dollar's value. It was right after President Nixon abandoned the gold standard that year. It allowed the value of the dollar to float freely in the world's foreign exchange markets. Before the creation of the dollar index, the dollar was fixed at $35/ounce of gold. It had been that way since the 1944 Bretton Woods Agreement.

The dollar index began at 100. The index has measured the percent change in the dollar's value since then. It changes constantly in reaction to shifts in the ongoing forex trades. For example, its all-time high was 163.83 on March 5, 1985. That meant the dollar was 63.83 percent higher than in 1973.

Its all-time low was 71.58 on April 22, 2008. That meant it was 28.42 percent lower than its inception. (Source: "DX.F" from Stooq.com. "USDX," ICE Futures.com.)

In 1985, the ICE Futures U.S. took over the management of the USDX. That's the year that futures trading on the USDX began. 

Historical Data

Here is U.S. dollar index® historical data, as measured by the DXY, for the last 10 years.

2007: The dollar's value, as measured by the DXY spot price,  was 76.20 on December 31.

2008: The dollar ended the year at 82.15 after falling to a low of $72.17 on March 31, 2008. That was shortly after the Bear Stearns bailout signaled damage from the Subprime Mortgage Crisis. At that time, investors thought it only affected the U.S., and bought euros. By the end of the year, it was clear the 2008 financial crisis was worldwide. The Fed lowered the fed funds rate 8 times. It initiated quantitative easing on November 25. Investors returned to the dollar as a safe haven.

2009: The DXY ended the year at 77.92. Dollar fell as euro rose once the European Central Bank began lowering rates.  

2010: The DXY rose to 86.04 on June 30, but ended the year at 78.96 despite Fed's launch of QE 2 on November 3.

2011: The DXY fell to 74.52 on June 30 due to U.S. debt default crisis.

Investors returned to the dollar due to eurozone crisis. Fed launched Operation Twist in September.  DXY ended the year at 80.21.

2012: Fed announced QE3 on September 13 and QE4 in December. The DXY closed at 79.678.

2013: On June 19, Fed Chair Bernanke announced the Fed would taper off QE purchases. Investors sold bonds in a panic, driving the yield on the 10-year Treasury note up 1 percent. The Fed delayed tapering until December. The DXY closed the year at 80.392. 

2014:  The dollar remained stable for the first six months, hitting 80.187 on July 11. The Ukraine crisis and Greek debt crisis drove investors out of the euro and into the dollar as a safe haven. The Fed ended QE in October. It held an unprecedented $4.5 trillion in Treasury notes.  It announced it would raise the fed funds rate in 2015.

The dollar rose to 90.030 by year end.

2015: The European Central Bank announced it would begin QE in March. The euro fell to $1.0524 on March 12. The USDX hit a 52-week high of 100.390 on March 13, 2015. The dollar had strengthened 25 percent from its 2014 low.  The Fed raised its benchmark rate to 0.5 percent on December 17, 2015.

2016: The dollar opened the year at 98.38. By April 24, it drifted to its 2016 low of 93.08. On December 11, it reached the year's high at 102.95. On December 14, the Fed raised the fed funds rate to 0.75 percent.

2017: Hedge funds began shorting the dollar. Europe's economy was improving, strengthening the euro. On June 14, the Fed raised the fed funds rate to 1.0 percent on March 15, and 1.25 percent. On June 25, the USDX fell to 96.05. On July 20, the European Central Bank signaled it might be ready to end QE in the fall. The dollar fell further to 91.84 on September 15, 2017.  (Source: "DXY Interactive Chart," Marketwatch. Its earliest record is 2007.)

Historical Chart (Using DX.F)

Year (last business day)DX.F CloseFactors Driving Dollar's Value
1967 121.79Gold standard kept dollar at $35/oz.
1968 121.96
1969 121.74Dollar hit 123.82 on 9/30.
1970 120.64Recession.
1971 111.21Wage-price controls.
1972 110.14Stagflation.
1973 102.39Gold standard ends. Index created in March.
1974   97.29Watergate.
1975 103.51Recession ended.
1976 104.56Fed lowered rate.
1977   96.44 
1978   86.50Fed raised rate to 20% to stop inflation.
1979   85.82
1980   90.39Recession.
1981 104.69Reagan tax cut.
1982 117.91Recession ended.
1983 131.79Tax hike. Increased defense.
1984 151.47
1985 123.55Dollar high was 163.83 on March 5.
1986 104.24Tax cut.
1987   85.66Black Monday.
1988   92.29Fed raised rates.
1989   93.93S&L Crisis.
1990   83.89Recession.
1991   84.69Recession.
1992   93.87NAFTA approved.
1993   97.63  Balanced Budget Act.
1994   88.69 
1995   84.83Fed raised rate.
1996   87.86Welfarereform.
1997   99.57LTCM crisis.
1998   93.95Glass-Steagall repealed.
1999 101.42Y2K scare.
2000 109.13Tech bubble burst.
2001 117.21Dollar rose to 118.54 on 12/24 after 9/11 attacks.
2002 102.26Euro launched as a hard currency at $.90.
2003    87.38Iraq WarJGTRRA.
2004   81.00 
2005   90.96War on Terror doubled debt. It weakened dollar.
2006   83.43
2007   76.70Euro rose to $1.4718.
2008   82.15Dollar hit record low of 71.58 on April 22.
2009   78.28Euro rose when ECB lowered rates. 
2010   79.31QE2.
2011   80.56Operation Twist. Debt default crisis.
2012   79.87QE3 and QE4. Fiscal cliff.
2013   80.21Taper tantrum. Government shutdown. Debt crisis.
2014   90.28Ukraine crisis. Greek debt crisis.
2015    98.65Dollar rose 25 percent since July 2014. See Dollar Strength.
2016 102.62Fed raised rates.

(Note: For data earlier than 2010, I used the DX.F from Stooq.com.  It is a futures indicator that at least gives you an idea of where the dollar stood compared to its history. If you have historical data from a better source, please email me at kimberly@worldmoneywatch.com.)

U.S. Dollar Index® FAQ