This is because every year this assistant professor receives a substantial salary increase ,part of which may be added to the base salary, base on her outstanding and research performance . On the other hand, the other assistant professor may still be making the same amount, or close to the same amount, he was making when he was first hired. Under a traditional pay plan, an assistant professor would not receive a higher salary than most associate professor. Under such a plan, the assistant professor would have to be promoted to associate professor before she could receive a salary of &110000, which is outside the traditional range for assistant professors.