Differential Cost and Revenue
Costs and revenues that differ among alternatives.
Example: You have a job paying $1,500 per month in your hometown. You have a job offer in a neighboring city that pays $2,000 per month. The commuting cost to the city is $300 per month.
Differential revenue is:
$2,000 – $1,500 = $500
Differential cost is:
$300
Differential costs (or incremental costs) is a difference in cost between any two alternatives. Differential costs can be either fixed or variable. A difference in revenue between two alternatives is called differential revenue.
For example, assume you have a job paying $1,500 per month in your hometown. You have a job offer in a neighboring city that pays $2,000 per month. The commuting cost to the city is $300 per month. In this example, the differential revenue is $500 and the differential cost is $300.
Opportunity Cost
The potential benefit that is given up when one alternative is selected over another.
Example: If you were not attending college, you could be earning $15,000 per year. Your opportunity cost of attending college for one year is $15,000.
Opportunity cost is the potential benefit that is given up when one alternative is selected over another. These costs are not usually entered into the accounting records of an organization, but must be explicitly considered in all decisions.
Sunk Costs
Sunk costs have already been incurred and cannot be changed now or in the future. These costs should be ignored when making decisions.
Example: Suppose you had purchased gold for $400 an ounce, but now it is selling for $250 an ounce. Should you wait for the gold to reach $400 an ounce before selling it? You may say, “Yes” even though the $400 purchase is a sunk costs.
A sunk cost is a cost that has already been incurred and that cannot be changed by any decision made now or in the future. Since sunk costs cannot be changed and therefore cannot be differential costs, they should be ignored in decision making. While students usually accept the idea that sunk costs should be ignored on an abstract level, like most people, they often have difficulty putting this idea into practice.