Hi,
Create new condition types (OBQ1) for 70% & 60 % of net value , with access sequence, say plant or company code. Now add the two conditions in the tax procedure just after calculated call, with from & to as the BASB step number and with statistical tick mark. Add new condition type, if required for the vat on 70% and ST 0n 60%.
Create a new tax code. Now maintain the condition record for the new condition types as 70% and 60% respectively as per requirement. Also create the condition records for VAT/ST condition types.
Hope the concept is clear and its helpful. Revert back in case of any doubts.
Regards,
AKPT