Hello anu,
I have had a look at your file and the article on Chandoo that dealt with this particular workbook.
One of the problems is that the workbook has been set up to do a very specific comparison between just two years data with the data alternating between rows. This in no way matches the sort of data layout that you seem to be implying that you want to compare.
I think you would be better to try to use PivotTable(s) to get some real data into the sort of format that you want for charting and then use a worksheet change macro to change the parameters in the Pivot table(s). I think this strategy was used in one of the responses to one of your other queries.
The other thing is, when you post a spreadsheet, it would be helpful to have some realistic data and data layouts to work with, with a correspondence between what you put in your post and the data that is in the worksheet.
sales-trend-analysis.zip
I have inserted a pivot table on the data sheet to get you started on this approach and I changed some cells on the calculation page (they now show other than #N/A or 0) to show just some of the changes that would be required just to see some data without necessarily making the system to be as flexible as you want.
I hope this gets you on your way and when you have some real data and a better indication of what exactly it is that you are needing perhaps I can have another look at it if you get stuck.
Regards
Harry