In the following video, Fool contributor Demitrios Kalogeropoulos discusses three reasons why United Parcel Service (NYSE:UPS) can keep delivering solid returns to shareholders despite a sluggish global economy. Demitrios highlights promising e-commerce trends, efficiency gains, and rising cash levels as the best reasons to invest in UPS right now. But the biggest upside for investors going forward, he says, is in rising profits from the company's U.S business.