“sequence of returns risk.”

"Over the 26-year period from 1973 through 1999, the S&P 500 Index provided a nominal return of 13.9% a year and a real return of 8.2% a year. With hindsight, you might think that, given the 8.2% real return, it would have been safe to withdraw 7% a year in real terms (that is, take 7% of the portfolio’s starting value and increase the withdrawal by the inflation rate each year). Unfortunately, had you retired at the end of 1972 and followed that strategy, you would have run out of funds within 10 years, by the end of 1982. This was because of “sequence of returns risk.” Adverse returns in the early stages of retirement are particularly harmful; the S&P 500 Index lost almost 40% in the 1973-1974 bear market."