The "Poor Man's Coppock" is an indicator I developed empirically to mimic the Coppock for those without charting software that draws it and without Microsoft Excel or a spreadsheet program to read Excel files.
The steps in its calculation are:
1. Calculate a 10 month simple moving average
2 Calculate a 20 month simple moving average
3. Subtract the 20 month moving average from the 10 month moving average
4. Plot the resulting oscillator.
I must stress that this is a rough-and-ready version and I cannot guarantee that it will always mimic the Coppock indicator as well as it has appeared to in the past.
If you do not have appropriate charting software that will run the Coppock, I really suggest that you use the spreadsheets that I publish on the Data Files page of my free access website. I update them at the end of every month, which is when the calculations are done for this long-term indicator.
If you do not have a spreadsheet program, I am happy to send you a pdf file of the spreadsheet, which is set out with all the steps for manual calculation across the top. You could then keep it up-to-date by hand. You only have to calculate one line of figures at the end of each month. Specify which index you want the file for from the list on the Data Files page of my web site.