Stocks ended last week on an abysmal note. The S&P 500 Index (SNPINDEX:^GSPC) lost 2% on Thursday, then another 1% on Friday, as a sell-off in high-growth names, tech and biotech companies drove the market lower. Thankfully, Wall Street bounced back on Monday as March U.S. retail sales beat estimates. But retail sales didn't impress investors in Intuitive Surgical, (NASDAQ:ISRG), Delta Air Lines (NYSE:DAL), and Pitney Bowes (NYSE:PBI), each of which in the troughs of the benchmark index today. The S&P itself added 14 points, or 0.8%, to end at 1,830.

Intuitive Surgical shed 3.3%, as investors still appear unable to get over last week's revenue warning. While the robotic medical devices company doesn't report official first-quarter results until April 22, it released preliminary, unaudited results last week. The 24% sales slump, driven by poor results from its da Vinci systems division, doesn't bode well for the company. The da Vinci systems segment is seen as the catalyst for growth, so it's no wonder Wall Street cringed at the 59% decline in the area. That said, the next generation of the robotic surgery device, the da Vinci Xi, was approved by the FDA earlier this month, and it should reinvigorate the company's prospects. 

Source: company website

Similar to Intuitive Surgical, shares of Delta Air Lines are also reeling from last week's sentiments. Stock in the airliner fell 2.4% today, bringing its three-day losses to 8.6%. Delta Air Lines shares began to slip after Imperial Capital lowered earnings estimates for American Airlines last Thursday, claiming the company had yet to factor in the effects of winter weather on results. The pullback doesn't seem fair to Delta, which reported that passenger unit revenue, a common and widely followed metric for airlines, increased 1% in March 2014 from March 2013. 

Pitney Bowes shares, too, have been through a rough three-day period. Off 6% in the last three sessions, the stock dropped 2% Monday. The mail processing equipment provider isn't just in a short-term pickle: its long-term prospects don't look so hot, either. As snail mail continues to slowly perish, so too do Pitney Bowes' sales. The company either needs to expand its offerings, boost its margins, or face its demise head-on. Judging by its results, Pitney Bowes is opting for the latter choice: sales have declined at an accelerating rate for the past four years, slumping 21% in 2013 alone.