How to dynamically format a paretto chart

[katdbc]

Hello ppl,

Im using a list report with a paretto chart .

I also have a prompt page which passes two parameters
one is the month and another is the product.

So for  the particular product, the report shows the number of backlogs and its reflected in a Pareto chart.

So how do i dynamically set the format for the maximum,minimum and interval value for the Y axis.

for eg: when i have 0- 300 as the range for the Y axis,
for one product the highest value is y axis is 240 and for the few others the max values are more than 300 ,so it looks the same for every  month.

Can you please help me this issue.I am really running out of time and in a pressure.

Thanks everybody