cost driver(In a system of activity-based costing, any factor such as number of units, number of transactions, or duration of transactions that drives the costs arising from a particular activity When such factors can be clearly identified and measured, they will be used as a basis for allocating costs to cost objects. The term cost driver is therefore effectively synonymous with both activity measure and allocation base and the literature often uses them interchangeably. OB&M Alexander Demidov)