One way to view the benefits of diversification into other assets

One way to view the benefits of diversification into other assets
than stocks is to look at the returns for a portfolio of stocks,
bonds, commodities, and cash over time—for example, over the
past 10 years. The surprise here is not that an all-stock portfolio
did better over the long run. The surprise is that the diversified
portfolio did not do badly at all, in comparison. And it proved to
be less volatile. So there may have been a few more restful nights
for the investors who were diversified, although it is quite true
that they would have had fewer parties in the late 1990s.