Assume that we know that for the period 1926–2010 the yield component for common stocks was 3.99 percent and that the cumulative wealth index was $2,420.46. The cumulative wealth index value for the yield component was (1.0399)⁸⁵ = 27.82. 

The cumulative wealth index value for the price change component was $2420.46 / 27.82 = 87.00.

The geometric mean annual average rate of return for the price change component for common stocks was (87.00)^1/85 = 1.0539.

The geometric mean for common stocks is linked to its components by the following:

1.0399 (1.0539) = 1.096; 1.096 - 1.0 = 0.096 or 9.6%

The cumulative wealth index can be found by multiplying together the individual component cumulative wealth indexes:

$87.00($27.82) = $2,420.34^*