How system will know whether this employee salary is 14000 / 16000 for the month are you maintaing 14000 in any wage type in IT 0008 for calculating the Indirect valuation of other wt's.
you maintain constant value in the system for wt basic, medical, conveyance and HRA is % of Basic now spl. allowances has to be automatic entry you need. means how system will know for this month how much has to pay ?
some where you have to state month salary and from that minus of the remaining wt's.