excise amt split on profit center basis

Hi SAP Gurus,

I have the following billing line item for revenue

sale of goods

Conversion charges

Fixing charges

TOTAL

Excise

Here all three revenue items go to a different profit center. The excise is calcultaed on the total of the three revenue. Client want the excise amount should be split in proportion of the revenu item.

How I can address this issue.

CHEERS