U.S. stocks fluctuated as GE (GE) - Get Report headlined a busy morning for deals news and crude oil tumbled below $48 a barrel. The energy sector was the worst performer on Wall Street. Business activity in the Chicago area weakened in October, according to the latest reading on Chicago PMI. The measure fell to its lowest level since May and fell short of analysts' forecasts of a slight increase. Constellation Brands (STZ) - Get Report agreed to purchase a Grupo Modelo brewery in Mexico for $600 million. The brewery will be used to ramp up production of Constellation's high-end Mexican beers. Modelo is a subsidiary of Anheuser-Busch (BUD) - Get Report . Lumber Liquidators (LL) - Get Report slumped after reporting a far wider quarterly loss than expected. However, the flooring company did show signs of recovery following last year's health and safety scandals.