Buoyant oil prices since Donald Trump's election have provided no lasting halo effect for energy stocks as the sector's profit rebound has lacked vigor, but that could change in the week ahead with a fresh crop of quarterly scorecards. Helped by OPEC output cuts, oil prices are up roughly 20 percent since Trump's victory, and U.S. crude has held above $50 a barrel since mid-December. "We are seeing a little bit of a difference of opinion between equity investors and commodity investors," said David Lefkowitz, senior equity strategist at UBS Wealth Management Americas in New York.