You could take the absolute worst case scenario if you want, I guess, but every other peak in the history of world markets has come back faster than that... Besides, that's not even fair. Why are you assuming the parent is talking about holding stocks bought at the peak? The kind of people that hold their stocks for years tend to be the kind of people who don't buy at a peak. Long-termers tend to be more of the Buffett persuasion; he has said that he wouldn't care if the market completely closed for 10 years, because he buys businesses that grow in good times and bad, and he collects dividends in good times and bad. All the while the employees of the companies are spending their efforts in making his stock more valuable.