Islamic bank licensees must develop and maintain an informed judgment about an appropriate level of the balances of PER, bearing in mind that its essential function is to provide mitigation of displaced commercial risk. Some Islamic bank licensees must maintain the proportion relating to IAHs in this reserve within the IAHs equity, with the purpose of smoothing returns to IAHs, and in particular, to enhance their returns if these are below those of competitors. This implies that there will be years in which the balance of this reserve will be increased, and others in which it will be depleted.