<prompt> Human: How does that work? Have these been around long enough to judge how well people have been able to plan for a date, compared to, say a total stock market index fund?  <response>: All those Target Date funds do is shift portfolio risk from higher to lower as you approach that date. For example, people who would buy into Target Date - 2050 funds are younger people who can accept more risk. Therefore, the portfolio contains more stock than bonds or cash. As 2050 draw closer, that funds portfolio will reduce risk by buying more bonds and cash while reducing ownership in stocks. Theres no real goal of maximizing returns in these funds, per se. Just utilizing age as a way to balance risk. 