Bogle created the first index mutual fund almost 40 years ago. On the last day of 1975, Vanguard's First Index Investment Trust was launched with assets of $11 million. Vanguard Group now manages $2 trillion in mutual and exchange-traded funds.
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Bogle told CNBC that traders want to "duke it out with other investors and they think they are smarter or stronger." He cautioned investors to stay away from trading and focus on long-term investing.
Long-term investors not only capture the market's returns, but the returns of American businesses over time.
"That's a growth proposition so long as this nation continues to grow, which I suspect, despite challenges, will be a long time," Bogle said.
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Those investors should hang on to their holdings "in thick and thin," despite the fact that he thinks the market may be on the verge of as much as a 25 percent decline.
"I think the best advice for investors is to ride it out and stay the course."
That means about 65-70 percent in stocks and 30-35 percent in bonds, and becoming weighted heavier in bonds later as the investor lives off the income.