Given the current landscape, with central banks in the U.S., Europe, the U.K. and now Japan executing various methods of quantitative easing, Koester warns that companies need to be more mindful than ever of the real-time impact of foreign exchange fluctuations on their bottom line.

FORBES: How Corporate Profits Suffer From Currency Wars

The standard line from the academic literature is that central bank intervention in foreign exchange works only when it's in line with the fundamentals - and even then, only when lots of central banks work together.

BBC: Swiss move to make its safe-haven less attractive

The supply of dollars on the foreign exchange market is reflected in debits (above the line) in the balance of payments.

FORBES: Strengthening Of The Yen Shows How We Misunderstand Exchange Rates

McDonald's reported strong same-store sales gains for May, but the company warned that foreign exchange swings -- particularly from the euro -- will hurt its bottom line.

FORBES: Magazine Article

Whirlpool, the maker of appliances under household names like KitchenAid, Maytag and its eponymous brand, is up nearly 60% over the last 12 months, and at a time when many companies are struggling to find top-line growth, sales were up 5% excluding the impact of foreign exchange and Brazilian tax credits.

FORBES: Stocks Smacked, But Whirlpool Shines Thanks To Housing Lift