Related: Why Relative Value Investing is Simpler Than Ever

Still, some investors apparently need convincing about veracity of the small-cap rally because IWM has seen $3.91 billion in departures this year.

For investors looking for continued upside in U.S. equities over international equities, the Direxion FTSE Russell US Over International ETF (NYSEArca: RWUI) offers them the ability to benefit not only from domestic U.S. markets potentially performing well, but from their outperformance compared to international markets.

Conversely, if investors believe that international markets will outperform U.S. domestic markets, the Direxion FTSE International Over US ETF (NYSEArca: RWIU) provides a means to not only see international markets perform well, but a way to capitalize on their outperformance compared to the U.S. markets.

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