Shares of McKesson (MCK) have been strong performers lately, with the stock up 5.5% over the past month. The stock hit a new 52-week high of $508.09 in the previous session. McKesson has gained 9% since the start of the year compared to the 3.6% move for the Zacks Medical sector and the 1.8% return for the Zacks Medical - Dental Supplies industry.What's Driving the Outperformance?The stock has a great record of positive earnings surprises, as it hasn't missed our earnings consensus estimate in any of the l ...