Cost Hierarchies
A cost hierarchy categorizes various activity cost pools on the basis of the different types of cost drivers, cost-allocation bases, or different degrees of different in determining cause-and-effect (or benefits-received) relationships. ABC systems commonly use a cost hierarchy with four levels to identify costs-allocation bases that are cost drivers of the activity cost pools: (1) output unit-level costs, (2) batch-level costs,(3) product-sustaining costs, and (4) facility-sustaining costs.