[1] The general formula to calculate residual risk is where the general concept of risk is (threats × vulnerability) or, alternatively, (severity × probability).
An example of residual risk is given by the use of automotive seat-belts.
Installation and use of seat-belts reduces the overall severity and probability of injury in an automotive accident;[2] however, probability of injury remains when in use, that is, a remainder of residual risk.
In the economic context, residual means “the quantity left over at the end of a process; a remainder”.
In the property rights model it is the shareholder that holds the residual risk and therefore the residual profit.