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 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 company to watch right now is Ryanair (RYAAY). RYAAY is currently sporting a Zacks Rank of #2 (Buy), as well as an A grade for Value. The stock holds a P/E ratio of 13.66, while its industry has an average P/E of 18.09. RYAAY's Forward P/E has been as high as 15.78 and as low as 8.35, with a median of 11.79, all within the past year.

Another notable valuation metric for RYAAY is its P/B ratio of 3.04. The P/B is a method of comparing a stock's market value to its book value, which is defined as total assets minus total liabilities. This stock's P/B looks attractive against its industry's average P/B of 5.01. Over the past 12 months, RYAAY's P/B has been as high as 4.11 and as low as 2.17, with a median of 3.30.

If you're looking for another solid Transportation - Airline value stock, take a look at Controladora Vuela Compania de Aviacion, B. de C.V. (VLRS). VLRS is a # 2 (Buy) stock with a Value score of A.

Shares of Controladora Vuela Compania de Aviacion, B. de C.V. are currently trading at a forward earnings multiple of 10.40 and a PEG ratio of -2.17 compared to its industry's P/E and PEG ratios of 18.09 and 1, respectively.

Over the last 12 months, VLRS's P/E has been as high as 6,243.17, as low as -73,021.84, with a median of 10.33, and its PEG ratio has been as high as 644.96, as low as -7,543.58, with a median of -1.29.

Controladora Vuela Compania de Aviacion, B. de C.V. sports a P/B ratio of 2.60 as well; this compares to its industry's price-to-book ratio of 5.01. In the past 52 weeks, VLRS's P/B has been as high as 6.43, as low as 2.19, with a median of 3.53.

Value investors will likely look at more than just these metrics, but the above data helps show that Ryanair and Controladora Vuela Compania de Aviacion, B. de C.V. are likely undervalued currently. And when considering the strength of its earnings outlook, RYAAY and VLRS sticks out as one of the market's strongest value stocks.

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Ryanair Holdings PLC (RYAAY) : Free Stock Analysis Report

Controladora Vuela Compania de Aviacion, S.A.B. de C.V. (VLRS) : Free Stock Analysis Report

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