When InvestingPro's Fair Value models identified Citigroup (NYSE:C) as significantly undervalued in early April 2025, the banking giant's stock was trading at $57.93. Fast forward four months, and the stock has delivered an impressive 66% return, validating the power of data-driven valuation analysis. For investors seeking similar opportunities, InvestingPro's Most undervalued list continues to identify potential winners using the same proven methodology. Citigroup, one of the world's leading financial institutions with a market capitalization of $177.8 billion, demonstrated strong fundamentals when the Fair Value signal was generated. The company's revenue had reached $71.5 billion, with earnings per share of $6.42, suggesting significant upside potential despite mixed performance in the preceding months. The Fair Value analysis proved remarkably accurate, with the stock reaching its target range by late July 2025.