Investors should buy American equities over international stocks because the U.S. economy already holds a huge stake in global business, Jack Bogle, founder of The Vanguard Group, said on Monday.
American investors putting their money abroad face a "currency risk" as the dollar strengthens against various currencies, Bogle said. The euro, for instance, hit a 11-year low against the dollar last week before steadying on Monday.
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Exchange rates make Bogle wary of putting too much weight in stocks abroad.
"Don't go over 20 percent in non-U.S. securities because you earn your money in dollars, you spend your money in dollars, you save your money in dollars," he said.
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