How do I design a Workbook which gets values dynamically.

Dear Experts,

I have a requirement to design a workbook " For a particular product It should have to display revenues monthly wise in Line chart".

So I have gone to Bex Analyzer (in the variable screen I have provided "product" and for period of 6 Months( 01/2010 to 06/2010) ) and while designing Line chart have manualy provided the values of 6 Months and Key Figures. It shows me Line chart for 6 Months.

But my client requirement is to show the values of any period which he has selected.

How do I fullfill that requirement and I am doing this in 3.x version.

Please provide me the solution and do the needful.

Thanks,

Swathi.