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

What: Shares of Aflac (NYSE:AFL) slipped slightly today Barclays Capital downgraded the insurance giant from overweight to equal-weight.

So what: Along with the downgrade, analyst Jay Gelb lowered his price target to $67 (from $78), representing about 8% worth of upside to yesterday's close. So while contrarian traders might be attracted to Aflac's year-to-date price weakness, Gelb's call could reflect a sense on Wall Street that the company's earnings growth remains just too sluggish to trigger a significant rebound.

Now what: According to Barclays, Aflac's risk/reward trade-off is pretty balanced at this point. "We downgrade Aflac to EW from OW because we now expect its operating EPS growth through 2016 (excluding the impact of the yen) to be lower than the life insurance industry median, driven by a lack of margin expansion," said Gelb. "AFL will likely return the majority of annual earnings to shareholders but we anticipate slow EPS growth is unlikely to result in valuation multiple expansion." With Aflac shares off about 10% from their 52-week high and sporting a near-3% dividend yield, however, those short-term concerns might present patient Fools with a juicy long-term opportunity. 

Brian Pacampara has no position in any stocks mentioned. The Motley Fool recommends Aflac. 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.