Tax conditions in purchase register report

Hi all,

I am developing a Purchase Register Report, I have a small doubt regarding Tax conditions.

From which tables we will get the Tax Conditions like CST, SERVICE TAX, VAT etc.

Previously I have developed Purchase Requisition Report,in that I have used the FM    'CALCULATE_TAX_ITEM' to get the Tax Condition Values. But in this purchase register report I am getting wrong values for the same FM.

Please suggest me.

Regards,

Pradeep.