The graphs are about long term returns. And how are those returns calculated? Because if they used arthritic mean, it’s overstating the actual annualized return.
First, it does not "overstate" the annualized returns. It just brings a particular view of them, which is the "expected annual return" vs the "compoundable annual return". Both are perfectly equivalent and represent different ways to look at annual returns. I would expect most practitioners to expect the former.
Second, this debate is completely irrevant here, as all charts show cumulative returns based on a $1 investment.
