__Working as a nurse or a computer engineer for a salary are two examples of active income. In contrast, residual income is income from an investment that earns over the minimum rate of return. You get paid for work you completed once or are periodically overseeing. With residual income, you don’t have to be present or intricately involved to get paid.__

^{The above seems simple enough, but it’s pointless if it’s not put to work toward calculating the actual intrinsic value of the company. And since the residual income valuation formula is an absolute approach to company valuation, it discounts future earnings to get to the fair value of company stock. To calculate the value of the stock, one has to add the book value and the present value of expected future residual income, discounting the cost of equity (illustrated in the first formula below with the symbol . For the purposes of valuation calculation with formula 1, the company will presumably continue to evolve toward maturity, or constant growth. Formula 2 below is for calculating Terminal value. Constant growth () from year is presupposed, according to the PGM (Perpetuity Growth model). }