While Fools should generally take the opinion of Wall Street with a grain of salt, it's not a bad idea to take a closer look at particularly stock-shaking upgrades and downgrades -- just in case their reasoning behind the call makes sense.

What: Shares of Citigroup Inc (NYSE:C) gained about 1% this morning after Evercore Partners upgraded the banking giant from Equal Weight to Overweight.

So what: Along with the upgrade, analyst Andrew Marquardt raised his price target to $58 (from $53), representing about 14% worth of upside to Friday's close. While value investors might be turned off by Citigroup's solid return in 2013, Marquardt believes there's room to run given his forecast for continued operational improvement over time.

Now what: Evercore tweaked its 2014 EPS forecast for Citigroup from $5.34 to $5.23, but raised its 2015 estimate from $5.50 to $6.00. "While operating environment may indeed be more challenging in '14 with fewer levers to pull and some lingering concerns of emerging mrkts slowdown, we have an upward bias to U.S. econ recovery," noted Evercore. "Importantly, we think Citi can achieve its '15 fin goals, and shares should continue to revalue upward as mgmt delivers on its restructuring actions to improve expense run rate, capital deployment, and potentially better core top line growth over time."

With Citigroup shares continuing to trade at a price-to-book discount to the industry, betting on that improvement might not be a bad idea. 

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool owns shares of Citigroup. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.