Right now, Gates stands as the most likely candidate to reach that milestone. For its analysis, Oxfam researchers applied the average growth rate of the ultra-rich — 11 percent per year since 2009 — to Gates' current levels of wealth, which was about $84 billion at the time of the study. If his investments keep doing as well as they have, the 61-year-old billionaire could indeed become the world's first trillionaire.
But if Bezos' wealth continues to rise at the same clip, he could very well reach trillionaire status first.
Their fellow billionaire Mark Cuban has another prediction for who will first cross that finish line: entrepreneurs working with artificial intelligence.
"I am telling you, the world's first trillionaires are going to come from somebody who masters AI and all its derivatives and applies it in ways we never thought of," the star investor of ABC's "Shark Tank" told audiences at the SXSW Conference and Festivals.
Whether the title will be held by someone recognizable or someone currently toiling in obscurity in a lab, only time will tell.
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