We recently published 10 Big Names With Explosive Gains.  Southwest Airlines Co. (NYSE:LUV) was one of the top performers on Thursday. Southwest Airlines soared to a new four-year high on Thursday, jumping 18.70 percent to close at $48.50 apiece, as investors welcomed the end of an open-seating era following the company’s official adoption of assigned seating. At intra-day trading, the stock jumped to as high as $49.12 before paring gains to finish the session just up by 18.70 percent. Southwest Photo ...