Here at Zacks, we focus on our proven ranking system, which places an emphasis on earnings estimates and estimate revisions, to find winning stocks. But we also understand that investors develop their own strategies, so we are constantly looking at the latest trends in value, growth, and momentum to find strong companies for our readers.

Of these, perhaps no stock market trend is more popular than value investing, which is a strategy that has proven to be successful in all sorts of market environments. Value investors use fundamental analysis and traditional valuation metrics to find stocks that they believe are being undervalued by the market at large.

Luckily, Zacks has developed its own Style Scores system in an effort to find stocks with specific traits. Value investors will be interested in the system's "Value" category. Stocks with both "A" grades in the Value category and high Zacks Ranks are among the strongest value stocks on the market right now.

Repsol (REPYY) is a stock many investors are watching right now. REPYY is currently sporting a Zacks Rank of #1 (Strong Buy), as well as a Value grade of A. The stock is trading with P/E ratio of 5.40 right now. For comparison, its industry sports an average P/E of 10.32. Over the last 12 months, REPYY's Forward P/E has been as high as 5.64 and as low as 3.98, with a median of 4.63.

Value investors also frequently use the P/S ratio. This metric is found by dividing a stock's price with the company's revenue. This is a prefered metric because revenue can't really be manipulated, so sales are often a truer performance indicator. REPYY has a P/S ratio of 0.25. This compares to its industry's average P/S of 0.67.

Finally, our model also underscores that REPYY has a P/CF ratio of 2.39. This metric takes into account a company's operating cash flow and can be used to find stocks that are undervalued based on their solid cash outlook. REPYY's current P/CF looks attractive when compared to its industry's average P/CF of 5.77. REPYY's P/CF has been as high as 3.57 and as low as 2.11, with a median of 2.95, all within the past year.

Investors could also keep in mind YPF Sociedad Anonima (YPF), an Oil and Gas - Integrated - International stock with a Zacks Rank of # 2 (Buy) and Value grade of A.

Shares of YPF Sociedad Anonima are currently trading at a forward earnings multiple of 7.34 and a PEG ratio of 0.17 compared to its industry's P/E and PEG ratios of 10.32 and 1.15, respectively.

YPF's price-to-earnings ratio has been as high as 9.12 and as low as 2.22, with a median of 4.36, while its PEG ratio has been as high as 0.21 and as low as 0.09, with a median of 0.14, all within the past year.

Additionally, YPF Sociedad Anonima has a P/B ratio of 1.20 while its industry's price-to-book ratio sits at 1.54. For YPF, this valuation metric has been as high as 1.49, as low as 0.67, with a median of 0.84 over the past year.

These figures are just a handful of the metrics value investors tend to look at, but they help show that Repsol and YPF Sociedad Anonima are likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, REPYY and YPF feels like a great value stock at the moment.

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This article originally published on Zacks Investment Research (zacks.com).

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