But there is also a higher risk of disaster, owing to a seemingly inborn human tendency to extrapolate past returns. Investors could create a stock-market bubble, encouraging even more naïve investors to concentrate their personal retirement accounts in the stock market – and leaving them dangerously exposed when it crashes.
但是，鉴于人类天性似乎总喜欢推算过去的报酬，还是存在着很大的灾难风险。投资者可能会制造一个股票市场泡沫，鼓励更为无知的投资者们将他们的个人退休账户集中投于股票市场——一旦泡沫破裂就把危险留给他们。