A Mean Proportional Projects the 2000 DJIA Top From Three Previous Important Turning Points
The mean proportional between two numbers is the square root of their product.
For example: in the three term continuous proportion 2-4-8, 4 is the mean proportional. 8 x 2 = 16, 4 is the square root of 16.
Click this chart to see it full-size:
This chart illustrates:
There are 2656 days between the June 25, 1962 bottom, and the January 11, 1973 top.
There are 3694 days between the January 11, 1973 top and the August 25, 1987 top.
The square root of 2656 x 3694 = 3132.3
There are exactly 3132 days between the 1987 top and the January 14, 2000 DJIA top.