U.S. Stock Markets Plunge Because of Panic Over Greece

Fears that Greece's troubles could spread through the global financial system shook markets on Monday, driving U.S. stocks to their worst day of the year. U.S. stock markets lost $900 billion of value in a single day because of panic around Greece's impending default on a $1.8 billion loan to the IMF tomorrow. Investors fled from stocks in Europe and the U.S. and retreated to the safety of government bonds. In many ways, it looked similar to previous episodes in Europe's long-running debt crisis, except that this time, investors said, they weren't quite as worried. A series of events over the weekend have left Greece perilously close to defaulting on its debts. Greece's Prime Minister, Alexis Tsipras, said his government would hold a referendum on budget proposals made by the country's lenders.