This sounds like a standard spiel that financial advisors at your local bank are trained to give. Even aside from all the problems with this sort of 'analysis'

This sounds like a standard spiel that financial advisors at your local bank are trained to give. Even aside from all the problems with this sort of 'analysis' like using past to predict future, extrapolating from a small data set, etc, the fact that their computation of past returns has no reference to inflation should tell you that you'd be better off listening to someone else.