Rethinking Activity-Based Costing


Activity-based accounting looks great in the classroom, but too often fails in the field. In this Harvard Business Review excerpt, HBS professor Robert S. Kaplan along with Steven R. Anderson suggest a way around the obstacles.

Activity-based costing, ABC, would seem to be an accurate way for managers to assign costs to the customers and products that use a department’s services. But real-world use has shown ABC loses power in large-scale operations, and can be difficult to implement and maintain. In their HBR article, excerpted here, authors Kaplan and Anderson suggest the process be simplified through an approach they call “time-driven ABC.” Here’s an overview.

The solution to the problems with ABC is not to abandon the concept. ABC after all has helped many companies identify important cost- and profit-enhancement opportunities through the repricing of unprofitable customer relationships, process improvements on the shop floor, lower-cost product designs, and rationalized product variety. Its potential on a larger scale represents a huge opportunity for companies. Fortunately, simplification is now possible through an approach that we call time-driven ABC, which we have successfully helped more than 100 client companies implement, including those described in this article. In the revised approach, managers directly estimate the resource demands imposed by each transaction, product, or customer rather than assign resource costs first to activities and then to products or customers. For each group of resources, estimates of only two parameters are required: the cost per time unit of supplying resource capacity and the unit times of consumption of resource capacity by products, services, and customers. At the same time, the new approach provides more accurate cost-driver rates by allowing unit times to be estimated even for complex, specialized transactions.