text:  through the end of 2000, where over the course of 10 years, you ended up with less money if you invested in the S&P 500 than if you invested in bonds. That's always a possibility. One of my fears is that if you use the historical data to project the safety of that type of a strategy, then you are going to have false confidence about its ability to bail you out so that you can actually maintain that lifestyle later on in retirement.