End of service calculation excluding Unpaid Days

Dear Gurus,

Currently working in Saudi Payroll implementation, Client wants to use only the service days and deduct the unpaid absence for the End of Service(EOS) Settlement when the employee resigned or terminated by the company.

SAP BADI is available to deduct the the unpaid absences.

How do we capture the unpaid absence which used by the employee in the previous years, say 01.01.2010 to 15.01.2010 as 15 days in the settlement calculation.

Thanks in advance for your valuable inputs.

Yusuff