Shares of Quanta Services (PWR) have been strong performers lately, with the stock up 8.1% over the past month. The stock hit a new 52-week high of $483.29 in the previous session. Quanta Services has gained 11.1% since the start of the year compared to the 11.1% gain for the Zacks Construction sector and the 18.5% return for the Zacks Engineering - R and D Services industry.What's Driving the Outperformance?The stock has a great record of positive earnings surprises, having beaten the Zacks Consensus Esti ...