Pivot Table

I need ur help regarding a problem which i facing in Pivot table. I want to make a summary of creditor in which I show a detail creditors report transaction wise, I did make this report but in the last column I want to show the balance of each creditor transaction wise. how can i make this report , I used total in function in pivot table but that not worked.Waiting for ur prompt response. For example

Creditor Date Tr. No. Dr. Cr. Balance
AA & Co. 1-10-11 0030 10 10
5-10-11 0034 15 25
9-10-11 0037 06 19

TA & Co. 3-10-11 0031 11 11
4-10-11 0036 25 36
9-10-11 0038 11 25

Regards,
Tauqeer
Sr. Accountant
Al Hussan Group
Saudia Arabia