Personal residual income, often called discretionary income, is the amount of income or salary left over after debt payments, like car loans and mortgages, have been paid each month. For example, Jim’s take-home pay is $3,000 a month. His mortgage payment, home equity loan, and car loan are the following respective: $1,000, $250, and $200. Using a residual income calculator, Jim would calculate his RI to be $1,550 a month. This is the amount of money he has left over after his monthly debt payments are make that he can put into savings or use to purchase new assets.
In equity valuation, residual income represents an economic earnings stream and valuation method for estimating the intrinsic value of a company's common stock. The residual income valuation model values a company as the sum of book value and the present value of expected future residual income. Residual income attempts to measure economic profit, which is the profit remaining after the deduction of opportunity costs for all sources of capital.