[kenjackson]

I do think this is still pretty relevant. I'm not a portfolio theorist, but I believe a lot of modern asset allocation is structured around risk of short-term liquidity. That is why allocation becomes more stock heavy as you have more years until retirement (for retirement accounts).

I think a lot of people would say, "if you gave me 50 years, and a five year window in which to divest, you should definitely go all stock". I don't think that would be absurdly controversial. Looking at this data though, given the risk, it actually isn't a slam dunk.

Now this isn't to say that one shouldn't diversify among equities, but I suspect you'd see similar charts for random selection diversified among mutual funds/indices.

[jond2062]

What you are referring to is known as the "glide path." An investor in the early accumulation years starts off with a high allocation to equities and reduces it over time as they gets closer to retirement (thus reducing risk, in theory). However, I'm not sure I understand your comment as this concept that you are referring to is part of the point that I was trying to make.

What happens specifically to the S&P 500 would not be the primary concern for an investor whose portfolio consists of a wide variety of asset classes and who follows a glide path approach by reducing their allocation to stocks (and increasing their allocation to bonds) over time. Thus an investor using this approach would not be 100% invested in the S&P 500 at the beginning or the end horizon (or at any point in between) of their investment.

I guess my point is that even just adjusting this data to include a 60%/40% equity/bond portfolio, rebalanced annually would be a heck of a lot more useful for retirement planning.