Plain vanilla index ETFs that track the value factor are lagging their growth and momentum counterparts so far this year. While some market observers believe value stocks and funds can bounce back, potential investors should still look under the hood of these value stock ETFs as no two are created alike and offer varying performances.

The Guggenheim S&P 500 Pure Value ETF (NYSEArca: RPV) is a solid option among value ETFs. RPV’s large tilt toward financials could prove beneficial in a rising rate environment, its large position in the bond-esque utilities sector may weigh on the portfolio ahead.

The value play may be seen as a basic type of enhanced or smart beta ETF strategy that specifically targets value stocks that tend to trade at a lower price relative to fundamentals, like dividends, earnings and sales. Along with the simple pure value play, such as RPV, the other value-focused ETFs may also incorporate other factors in their screening process.

“The overall returns from a 10-year period have been in favor of RPV compared to the S&P 500. However, on a yearly return basis, RPV has seen some serious swings comparatively. For instance, notice how during the 2007-2008 period RPV was down over 50%. Ouch. On the plus side, they were up over 50% during the 2009 period. RPV went on to clobber the S&P 500 in year 2010, 2012, and 2013. Overall, if it weren’t for the massive beating in 2008, RPV would’ve absolutely destroyed the S&P 500,” according to a Seeking Alpha analysis of the ETF.

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Value stocks usually trade at lower prices relative to fundamental measures of value, like earnings and the book value of assets. On the other hand, growth-oriented stocks tend to run at higher valuations since investors expect the rapid growth in those company measures, but more are growing wary of high valuations, especially as the U.S. equities market moves toward the ninth year of an extended bull run.

“RPV is currently a good fund for investors who are seeking large cap value companies in their portfolio. It also has a substantial allocation to the cyclical sector, mainly financial services,” according to Seeking Alpha.

Value stocks have historically outperformed growth stocks, or companies with high earnings expectations, in almost every market over the long-haul. For instance, the MSCI USA Value Index has outperformed the MSCI USA Growth Index by an annualized 81 basis points since 1974 through September 2015.

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