You're wrong. If you only invested lump sums in the S&P 500 in 1998, 1999, 2005, and 2006, you'd have made money by today. Not as much as you would have histori

You're wrong. If you only invested lump sums in the S&P 500 in 1998, 1999, 2005, and 2006, you'd have made money by today. Not as much as you would have historically, but still a fair chunk - and while yes, inflation would have eaten a large, large portion of it, it's way better than leaving your cash under your mattress. There's no way you lost money if you were in the S&P 500, unless you were pulling it out of investments after crashes - in which case, duh, you're buying high and selling low, what did you expect? And that's if you were only in the S&P 500... a more reasonable retirement portfolio is much more diversified, which would have increased your returns and lowered your volatility. http://stockcharts.com/freecharts/perf.php?SPY http://stockcharts.com/freecharts/perf.php?SPY