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.

Looking at the history of these trends, perhaps none is more beloved than value investing. This strategy simply looks to identify companies that are being undervalued by the broader market. Value investors rely on traditional forms of analysis on key valuation metrics to find stocks that they believe are undervalued, leaving room for profits.

In addition to the Zacks Rank, investors looking for stocks with specific traits can utilize our Style Scores system. Of course, value investors will be most interested in the system's "Value" category. Stocks with "A" grades for Value and high Zacks Ranks are among the best value stocks available at any given moment.

One company to watch right now is Oasis Petroleum (OAS). OAS 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 5.24 right now. For comparison, its industry sports an average P/E of 8.26. Over the past 52 weeks, OAS's Forward P/E has been as high as 20.66 and as low as 4.49, with a median of 6.08.

We should also highlight that OAS has a P/B ratio of 2.42. Investors use the P/B ratio to look at a stock's market value versus its book value, which is defined as total assets minus total liabilities. OAS's current P/B looks attractive when compared to its industry's average P/B of 3.18. Over the past 12 months, OAS's P/B has been as high as 2.46 and as low as 1.24, with a median of 1.98.

Value investors also love the P/S ratio, which is calculated by simply dividing a stock's price with the company's sales. This is a prefered metric because revenue can't really be manipulated, so sales are often a truer performance indicator. OAS has a P/S ratio of 1.74. This compares to its industry's average P/S of 2.77.

Finally, our model also underscores that OAS has a P/CF ratio of 6.40. 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. This stock's P/CF looks attractive against its industry's average P/CF of 10.37. OAS's P/CF has been as high as 6.52 and as low as 1.53, with a median of 2.29, all within the past year.