The contrast either to Apple Computer's HRIS, which is designed to be by every employee in the company, or to system that serve a single function, a third kind of HRIS has been developed specifically for use by upper-level executives. Systems of this third kind are sometimes referred to as executive information systems (EISs). For example, after a corporate restructuring eliminated several layers of management, Phillips Petroleum installed an EIS in order to support its managers and increase their span of control. The company estimates that its system was able to save over $100 million by decentralizing decision making and delivering needed information directly to the managers.