However, with passive income, there is not a direct connection to time involved. Once the original work is completed, the income continues to come in as long as demand for the product or service exists. Each time a song is downloaded, the musician receives money as a passive income. They did not have to record the song again or do additional work for each download, yet they are paid for their original work.
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.