As S&P 500 flops, investors flock to this ETF

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Editor's Note: Matt Hougan is chief executive officer of The following story is part of an exclusive column in which Hougan finds investment trends for CNBC Pro subscribers.

Currency-hedged ETFs are all the rage, and the WisdomTree Europe Hedged Equity ETF (HEDJ) is the leader of the pack. The fund has attracted more than $14 billion in net new money this year, as investors seek to make a bet on European stocks without taking on exposure to the euro.

So what's so great about currency-hedged exposure?