How can I make sure I don’t lose money in the stock market?

You’re less likely to lose money in the stock market if you own more stocks and you hold them for a long period of time. If you owned an S&P 500 mutual fund that holds the 500 largest company stocks in the U.S., you would have never lost money if you held it for at least 15 years – whether you bought it in 1973, 1983, 1993, or 2003 or any year in between!

More info: The Best And Worst Rolling Index Returns