In their article “Activity-Based Systems: Measuring the Costs of Resource
Usage,” Kaplan and Cooper argue that a company should have two different reporting
systems, the periodic financial statement and the ABC-based cost system, since they
provide different information to management. The periodic financial statement gives
information about the cost of activities supplied each period, and the ABC-based cost
system provides information about both the estimated cost and the quantity of activities
that are actually used in a certain period. The difference between the amount of activity
supplied and the amount of activity used gives the amount of capacity that is not used
during the period. This relation can be explained more clearly by the following fo