The main properties of the geometric mean are:
- The geometric mean is less than the arithmetic mean, $$G.M < A.M$$
- The product of the items remains unchanged if each item is replaced by the geometric mean.
- The geometric mean of the ratio of corresponding observations in two series is equal to the ratios of their geometric means.
- The geometric mean of the products of corresponding items in two series is equal to the product of their geometric mean.