In the investment world, it’s common to discuss average rates of return. It’s not sufficient, however, to simply add up historical returns and divide by how many there are.

When talking investment portfolios, the geometric mean is also sometimes referred to as compounded annual growth rate or time-weighted rate of return.

Kirkland B. Stewart, Situations in Which the Arithmetic and Geometric Moving Averages Are Inefficient Estimators, Technometrics, Vol. 14, No. 3 (Aug., 1972), pp. 619-633 ...