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.

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.

One stock to keep an eye on is Aviva (AVVIY Quick QuoteAVVIY - Free Report) . AVVIY is currently holding a Zacks Rank of #2 (Buy) and a Value grade of A. The stock holds a P/E ratio of 6.90, while its industry has an average P/E of 8.55. AVVIY's Forward P/E has been as high as 7.28 and as low as 3.33, with a median of 5.37, all within the past year.

Another notable valuation metric for AVVIY is its P/B ratio of 0.75. 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 1.32. Over the past year, AVVIY's P/B has been as high as 0.88 and as low as 0.40, with a median of 0.61.

These are just a handful of the figures considered in Aviva's great Value grade. Still, they help show that the stock is likely being undervalued at the moment. Add this to the strength of its earnings outlook, and we can clearly see that AVVIY is an impressive value stock right now.