Related: As USD Strengthens, Currency Hedged ETFs Require a Second Look

Obviously, UUP’s slack year-to-date showing indicates shorting the dollar has been the right way to play the U.S. currency. It may also imply that shorting the dollar has been easy. Moreover, the dollar’s 2017 struggles could be a sign that shorting the greenback is a trade with too many participants.

“But investors should beware of that benefit dissipating as the dollar reverses course. After bottoming in September, it has strengthened 4 percent against a basket of currencies. According to estimates by Goldman Sachs Group Inc., every 10 percent shift in the dollar affects S&P 500 Index earnings per share by $3,” according to Bloomberg.

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