Business Insider reports that billionaire Elon Musk has lost about $100 billion this year, the largest one year drop ever reported by the Bloomberg Billionaires Index. The Tesla, SpaceX and now Twitter CEO's net worth reached its lowest point in 2022 on November 22. Musk's net worth, which peaked at $340 billion last November, dropped to around $170 billion. The plunge was reportedly caused by Tesla shares falling to a two-year low on November 21. Musk's 15% stake in Tesla means that the billionaire lost about $8.6 billion in just one day as those stocks declined.