And since the Fed embarked on its latest round of stimulus, the dollar has lost ground.
Since Bernanke first hinted at quantitative easing in August, the dollar index -- which measures the greenback against a basket of other currencies -- has fallen 9%. Against the euro alone, the buck has tumbled 15%.
While a weaker dollar has some benefits -- it makes U.S. exports more competitive on the world stage, for example -- it can also fuel inflation, limit the purchasing power of Americans and drive up the price of dollar-priced commodities like oil.
For this reason, many critics blame higher gas prices on the Fed's quantitative easing program.
