هزینه یابی مبتنی بر فعالیت زمان محور: طراحی یک مدل در محیط تولیدی پرتغال Time-driven activity-based costing: Designing a model in a Portuguese production environment

1. Introduction Time-driven activity-based costing (TDABC) is a new ABC variant that enables you to build powerful and flexible cost models quite simply (Kaplan and Norton, 2008, p. 209). Described in the literature as a simple model, TDABC can be considered the next generation of activity-based costing (ABC). This new solution was designed by Kaplan and Anderson specifically to simplify the implementation process and the time-consuming and expensive maintenance of its forerunner ABC (Kaplan and Anderson, 2007a, 2007b; Tse and Gong, 2009; Balakrishnan et al., 2012b; Hoozée et al., 2012). Since then, the model has demonstrated great practical applicability (Everaert et al., 2012), given the countless examples of use and implementation in the literature (Everaert et al., 2008a; Kaplan and Norton, 2008; Demeere et al., 2009; Hoozée and Bruggeman, 2010; Giannetti et al., 2011; Kont and Jantson, 2011; Tanis and Ozypici, 2012; Campanale et al., 2014). These examples range from companies in the hotel sector (Dalci et al., 2010) to healthcare (Campanale et al., 2014) and even financial services (Kaplan and Norton, 2008). However, it seems that the literature has been mainly focused on companies related to services insofar as examples of TDABC models in manufacturing companies are scarce. This is curious, as Stratton et al. (2009) in their quantitative analysis showed that the model from which TDABC evolved has been implemented in manufacturing, and there are also published works on manufacturing companies using ABC (Anderson et al., 2002; Liu and Pan, 2007). Furthermore, TDABC is considered a model capable of handling the complexity and variability of daily activities (Everaert et al., 2008a). Could this be a trivial gap in the literature or is there another reason? In fact, to the best of our knowledge, only the study by Öker and Adigüzel (2010) illustrates a model in a manufacturing company and ends by concluding that TDABC is more suitable for service companies. This is because, as the authors say, in service companies, resources can be assigned through labour hours. However, using only this measure for manufacturing companies is difficult, as machinery time must also be considered, which means that two practical capacities must be calculated and two time equations must be created for each production process. Taking the results of Öker and Adigüzel (2010) as a starting point, we aim to examine in further detail the suitability and the complexity of building a model for manufacturing companies. To do so, we adopt an interventionist approach allowing us to take part in the model designing process from the very beginning, and thus collect more sensible, richer and detailed insights (Suomala et al., 2014). Based on this insider experience and on the model that resulted from the fieldwork, we then report the model and compare and discuss other models that are available in the literature for service companies. The host company in this study was GP (a fictitious name for the purpose of confidentiality), namely, a Portuguese company in the frozen food sector. Given the competitive environment in which GP operates, the managers felt the need to modify their costing practices and expressed interest in the researchers’ suggestion to design a pilot TDABC model for the company. Prior to this, a very rudimentary costing system had been used, which simply attempted to identify the cost of each production batch.