Shares of Affiliated Managers Group (AMG) have been strong performers lately, with the stock up 2.4% over the past month. The stock hit a new 52-week high of $168.63 in the previous session. Affiliated Managers Group has gained 8.2% since the start of the year compared to the 6.2% move for the Zacks Finance sector and the 8.2% return for the Zacks Financial - Investment Management industry.What's Driving the Outperformance?The stock has a great record of positive earnings surprises, as it hasn't missed our ...