The main advantage of the residual income metric is that it measures excess return earned by a department in absolute terms. A positive residual income means that the department has met the minimum return requirement while a negative residual income means that the department has failed to meet it. Return on investment (ROI) is another metric which measures return in relative terms.
Passive income is earnings derived from a rental property, limited partnership or other enterprise in which a person is not actively involved. As with active income, passive income is usually taxable. However, it is often treated differently by the Internal Revenue Service (IRS). Portfolio income is considered passive income by some analysts, so dividends and interest would therefore be considered passive.
Those who can reap the benefits of residual income have typically put in an immense amount of effort and time in the beginning to be able to enjoy the rewards later on. Residual income, therefore, does not result in instant gratification. Those interested in earning residual income must have a lot of patience and determination to work as hard as necessary to achieve their ultimate goals of a long-standing income stream.

Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.