S&P historical returns for 5 worst periods
Graph source: Robert Shiller
Drop over previous 5 years: 60.9 percent
The very worst five-year period, ending in 1932, captures the crash of 1929, when the stock market wiped out thousands of investors. That crash was followed by a rally in the spring of 1930, when the market gained 50 percent, yet 20 percent short of the peak. Business Insider CEO and former Internet analyst Henry Blodget calls the 1930 rally "the biggest sucker's rally in history." From there the market plummeted again, down 89 percent from the 1929 high.