Reasons for adopting different capacity levels in the denominator of overhead rates: a research note

There has been criticism of the use of budgeted capacity as the denominator of overhead rates. Prior questionnaire-based research has analysed which type of capacity is used in the denominator of overhead rates, but it has not assessed why these capacity levels are used. This paper uses grounded theory techniques to analyse 50 interviews with British management accountants about why a particular capacity level is used to determine the denominator of overhead rates. The results reveal that budgeted capacity is used because the calculation of the denominator is regarded as part of the budgeting process. Practical capacity and normal capacity are used to ensure that products are not under or overcosted.