Managing costs requires an understanding of opportunity costs and triggers that change costs. As stated earlier, opportunity costs usually are easy to assess. The opportunity cost of using $220 in supplies is $220. The opportu- nity cost of using an hour of legal time billed at $150 per hour is $150. Other cases demand more study. For example, the opportunity cost of a vacant wing of a hospital depends on its future use. If the wing will be reopened for acute care in response to a rising hospital census, the opportunity cost of the wing will depend on its value as an acute care unit. If the wing will be reopened because the hospital needs a skilled nursing unit, the opportunity cost of the wing will be determined by its value in that role.
Sunk costs should be ignored. A sunk cost is a cost you cannot change. A computer’s purchase price is a sunk cost, as is money spent to train employees to operate the computer. If your current needs do not require the use of a computer, you should not fret about its initial cost. The opportunity cost of the computer will depend on its value in some other use (including its resale value).