The causes of misapplied capacity related manufacturing costs and corresponding reporting implications: A conceptual perspective

To meet external financial reporting requirements, fixed (i.e., capacity related) manufacturing overhead costs are typically applied to inventory via the use of a predetermined overhead application rate. However, textbooks do not consider all appropriate conceptual issues regarding the setting of the overhead application rate nor how these issues influence the causes of misapplied capacity costs (under/over-applied fixed manufacturing overhead) typically reported as the Production Volume Variance. Specifically, discussion is lacking related to those misapplied capacity costs potentially caused variously by the presence of capacity that is not explicitly planned to be used, capacity that is currently unused but in the longer-term is planned to be used (due to anticipated growth), and capacity that is currently unused but in the shorter term is planned to be used due to seasonality. Determining if any of these three causes are contributing to misapplied capacity costs is critical, as there are important managerial accounting and financial accounting reporting implications associated with each. And while the relevant literature to be discussed offers support for these causal constructs, this paper extends this literature by developing a parsimonious and conceptually-based approach to permit a simultaneous partitioning of misapplied capacity costs into these causal categories. Further, this paper will identify the important conceptual differences among these three causes, how these differences warrant unique approaches for the managerial and financial reporting of information related to capacity costs and utilization, and needed changes to Generally Accepted Accounting Principles to facilitate more appropriate financial reporting in this area.

Research highlights
► Develops a conceptual model to partition the volume variance into multiple causes.
► Volume variance causes are seasonality, growth, idle capacity, estimation error.
► Illustrates volume variances caused by seasonality/growth will reverse over time.
► Discusses the managerial accounting implications for each volume variance cause.
► Discusses the financial accounting implications for each volume variance cause.