The U.S. Internal Revenue Service categorizes income into three broad types, active income, passive income, and portfolio income. It defines passive income as only coming from two sources: rental activity or "trade or business activities in which you do not materially participate." Other financial and government institutions also recognize it as an income obtained as a result of capital growth or in relation to negative gearing. Passive income is usually taxable.
Residual income is calculated as net income less a charge for the cost of capital. The charge is known as the equity charge and is calculated as the value of equity capital multiplied by the cost of equity or the required rate of return on equity. Given the opportunity cost of equity, a company can have positive net income but negative residual income.