While the proven Zacks Rank places an emphasis on earnings estimates and estimate revisions to find strong stocks, we also know that investors tend to develop their own individual strategies. With this in mind, we are always looking at value, growth, and momentum trends to discover great companies.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 use tried-and-true metrics and fundamental analysis to find companies that they believe are undervalued at their current share price levels.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.ASGN Inc (ASGN) is a stock many investors are watching right now. ASGN is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock is trading with P/E ratio of 14.18 right now. For comparison, its industry sports an average P/E of 28.19. Over the last 12 months, ASGN's Forward P/E has been as high as 18.19 and as low as 6.30, with a median of 14.03.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 popular metric because sales are harder to manipulate on an income statement, so they are often considered a better performance indicator. ASGN has a P/S ratio of 0.88. This compares to its industry's average P/S of 2.01.Finally, we should also recognize that ASGN has a P/CF ratio of 12.88. 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. ASGN's current P/CF looks attractive when compared to its industry's average P/CF of 36.28. Within the past 12 months, ASGN's P/CF has been as high as 14.47 and as low as 6.11, with a median of 12.96.These figures are just a handful of the metrics value investors tend to look at, but they help show that ASGN Inc is likely being undervalued right now. Considering this, as well as the strength of its earnings outlook, ASGN feels like a great value stock at the moment.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report ASGN Incorporated (ASGN): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research