Chande & Kroll's R2 indicator

Chande & Kroll's R2
In his book The New Technical Trader, Chande & Kroll introduced R2 indicator. They argue that "the primary use of R2 as a confirming indicator" and that "it is a lagging indicator that shows the strength of the trend."
In MetaStock the formula R2 is:
Pwr (Corr (Cum (1), C 14.0), 2)
They also represent smoothed R2 which will be:
Mov (Pwr (Corr (Cum (1), C 14.0), 2) * 100,14, S)
For interpretation refer to the book Chande & Kroll, as stated above.
Note: r squared indicator is built into MetaStock for Windows version 6.0.