The U.S. national debt sits at more than $11 trillion dollars -- double its total from just 10 years ago. That's so much debt that some are questioning the dollar's status as the world's reserve currency.

     But there is a silver lining for income investors. This massive spending, combined with movement out of U.S. Treasuries, is going to take its toll on the dollar, and international income investors could reap the rewards in the form of higher dividends. Read on to see just how much a falling dollar can boost your income stream.

     Living in Canada, I see first-hand the impact of the falling U.S. dollar. From 2002-2007, the Canadian dollar soared uninterrupted over its stateside counterpart.

     Over that time, it usually cost me less and less to purchase anything in U.S. dollars... whether it be investments or even vacations. Even though I was spending the same amount of money, my Canadian dollar simply went further in the United States.

     If you're living in the U.S., don't fret. You can take advantage of the same phenomenon by investing abroad. And if you're an income investor, you'll find that your dividends can soar because of it -- even if the underlying company doesn't raise them a cent.

     How Far the Mighty Fell

     From a peak in July 2001 to a low in April 2008, the U.S. Dollar Index fell by a staggering -41%. As world economic growth exploded, investors somewhat shunned the U.S. markets, instead focusing on developing nations with high growth prospects.

      Meanwhile, U.S. deficits began to soar at an astounding rate. Public debt ballooned over +50% from $6 trillion in 2000 to over $9 trillion in 2007. As you likely know, heavy debt loads can lead to instability in a company or a country. And with foreign markets booming while the United States racked up more and more debt, entities around the world demanded fewer dollars -- helping lead to its long-term decline.