Carlos Slim Helu: $50 billion

The Mexican tycoon owes his fortune to a major ownership in America Movil, a telecommunications multinational worth $42 billion. He personally owns about 7 percent in the company while his broader family retains a 37 percent stake. He was ranked as the richest person three years ago, but saw his net worth hit by a downturn in Latin American economies. President-elect Donald Trump's threats to scrap free trade deals and build a wall on the U.S.-Mexico border have also hurt shares in his business interests. Forbes estimates his net worth dropped $5 billion in the four days after Trump's election.