NPA means nonpractising allowance for all doctors. generally (BP+GP+NPA) all togethers come into calculation of increment, HRA,DA calculation as same rate. NPA varries from either 25% or 30% of (BP+GP).if it is not possible to calculate NPA easily then i can only request you plz make a manual option for NPA and where you calculate on basis of( BP+GP), now give option for (BP+GP+NPA). if there is no NPA then it delt as nil.