I have created a payroll system using Microsoft access 2003. I just want to ask on how do I automatically compute the SSS contribution, withholding tax automatically when I select the field ?SSS used bracket to know the contribution same thing with withholding tax.

My experience:-

I have in the past created a payroll system , subject to 50 employees,
Using EXCEL.
I found out it was very efficient
Especially you can fully control it.
You can incorporate all the necessary
Calculations quite easily.
Try and see how you go.