Price breaks at Purchase order header level

Hi,

Can price breaks be created at blanket purchase agreement header level ?

I could see, price breaks are available at BPA line level.

How to handle the below screnario.

We entered into an agreement with a supplier, such that in a year if we spend more than 100,000 USD, we are entitled to a 5% discount.

Remember this is overall spend with the supplier on any item.

How do i set this up in Oracle such that, oracle will automatically calculate this discount ?

Thank you,