Here at Zacks, our focus is on the proven Zacks Rank system, which emphasizes earnings estimates and estimate revisions to find great stocks. Nevertheless, we are always paying attention to the latest value, growth, and momentum trends to underscore strong picks.

Of these, value investing is easily one of the most popular ways to find great stocks in any market environment. Value investors use a variety of methods, including tried-and-true valuation metrics, to find these stocks.

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 stock to keep an eye on is Ranger Energy Services (RNGR). RNGR is currently sporting a Zacks Rank of #2 (Buy), as well as a Value grade of A.

Another notable valuation metric for RNGR is its P/B ratio of 1. 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. This stock's P/B looks solid versus its industry's average P/B of 2.24. RNGR's P/B has been as high as 1.29 and as low as 0.81, with a median of 0.92, over the past year.

Value investors also use the P/S ratio. The P/S ratio is is calculated as price divided by sales. This is a popular metric because sales are harder to manipulate on an income statement, so they are often considered a better performance indicator. RNGR has a P/S ratio of 0.46. This compares to its industry's average P/S of 0.92.

Finally, we should also recognize that RNGR has a P/CF ratio of 4.50. This metric focuses on a firm's operating cash flow and is often used to find stocks that are undervalued based on the strength of their cash outlook. This company's current P/CF looks solid when compared to its industry's average P/CF of 7.76. Within the past 12 months, RNGR's P/CF has been as high as 5.05 and as low as 3.51, with a median of 4.13.

Value investors will likely look at more than just these metrics, but the above data helps show that Ranger Energy Services is likely undervalued currently. And when considering the strength of its earnings outlook, RNGR sticks out at as one of the market's strongest value stocks.

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