Life cycle fund is a fund that can automatically adjust the asset allocation ratio according to the risk-return characteristics of investors in different life stages. In the early days, it mainly invested in equity securities, similar to equity funds, with a high level of risk and return; With the passage of time, the proportion of its investment in equity securities is decreasing, the proportion of its investment in fixed-income securities is increasing, and the risk-return level is gradually decreasing; After the target date, it eventually evolved into a partial debt fund with low risk and income level, even a money market fund, which brought stable income to investors. Lifecycle funds have developed rapidly in overseas markets. Since the launch of 1996, its scale has grown from the initial $600 million to 167 billion. By 2005, more than 64% of the 40 1(K) pension plan in the United States was invested in life-cycle funds, an increase of seven times in ten years.