Hi, I'm usually not stumped by PCF's but for some reason can't get my head around this one. I read the 2007 thread on it, but am still baflled. Here is a description from SafeHaven:

"The Coppock Curve is a monthly indicator which can be applied to various markets. For example, we can apply it to the Dow Jones Industrial Average.

To calculate the Monthly DJIA Coppock Curve all we need is the DJIA time series and a spreadsheet. Let's assume we have calculated the Monthly DJIA Coppock Curve for a few years. Let's assume further that the 100th month in the time series has just ended and now we want to calculate the Coppock Curve value for that month.

Here is the formula in plain English:

Step 1. We calculate the percentage change in the DJIA from Month 86 to Month 100 (from last close to last close).

Step 2. We calculate the percentage change in the DJIA from Month 89 to Month 100 (from last close to last close).

Step 3. We add the two percentages. We then keep this sum (and the 9 sums we previously obtained in the same way for the preceding 9 months) ready for weighting.

Step 4. Consider the weights 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Using multiplication, we assign these 10 weights respectively to the sums we attained in Step 3 for each month from Month 91 through Month 100. Month 91 will have a weight of 1. Month 100 will have a weight of 10. We then combine all 10 weighted sums in order to arrive at a weighted total.

Step 5. We multiply by 10 the weighted total obtained in Step 4. This gives us the Monthly DJIA Coppock Curve value for Month 100."

What would the PCF be? Thanks very much!