how to use the result to find the difference between 2 months

Hi,

I need to create one query which should show Order Qty and Weighted Price for current month and Previous month and difference like below:

Rows Current Month Previous Month Difference (current month-previous month)

Order Qty 20 10 10

Weighted Price 550 530 20.

Here Weighted Price for current month and previous month is not a straight forwad value ,it is based on formula and exception aggregation properties of the characteristics in the query. Now the issue is ,I am getting the correct difference for Order Qty ,because there is no formula involved. But for weighted price I am getting some different value(more than 500) instead of 20. I guess the difference is not just the difference of current month and previous month for the price. Instead it is a calculated value same like weighted figures for the current and previous month. But I really just want the difference of prices, not based on the formula.

I am not sure how to achive this in the query designer, Is there any solutions available to get the value for price to use the result of the formula?

Your help is very much appreciated.

Thanks for your time.

Thanks & Regards,

Raja