NEW YORK ( ETF Expert) -- The United States of America is frequently credited with being the largest economy in the world. Indeed, the U.S. produces the greatest market value of final goods and services per year.On the other hand, when an economy is not defined by national borders, the European Union can be credited with the largest Gross Domestic Product. It is this fact that financial markets may have been underestimating since July 26. Roughly one month ago, the president of the European Central Bank famously stated that policymakers will "do whatever it takes to preserve the euro." In fact, since Mario Draghi strongly hinted the ECB would be able to buy bonds in the way Ben Bernanke's Federal Reserve has done with its quantitative easing, both the CurrencyShares Euro Trust ( FXE) as well as Vanguard Europe ( VGK) have soared.