Cost Analysis purposes

For purposes of cost analysis, the desegregation of the generic value chain into individual value activities should reflect three principles that are not mutually exclusive:

•    The size and growth of the cost symbolized by the activity costs
•    The cost behavior of the activity
•    Competitor differences in executing the activity

Activities should be separated for cost analysis if they represent a significant or rapidly growing percentage of operating costs or assets. While most firms can easily identify the large components of their cost, they frequently overlook smaller but growing value activities that can eventually change their cost structure. Activities that represent a small and stagnant percentage of costs or assets can be grouped together into broader categories.

Activities must also be separated if they have different cost drivers. Activities with similar cost drivers can be safely grouped together. For example, advertising and promotion usually belong in separate value activities because advertising cost is sensitive to scale while promotional costs are largely variable. Any activity a business unit shares with others should also be treated as a separate value activity since conditions in other business units will affect its cost behavior. The same logic applies to any activity that has important linkages with other activities. In practice, one does not always know the drivers of cost behavior at the beginning of an analysis; hence the identification of value activities tends to require several iterations. The initial breakdown of the value chain into activities will inevitably represent a best guess of important differences in cost behavior. Value activities can then be aggregated or disaggregated as further analysis exposes differences or similarities in cost behavior. Usually an aggregated value chain is analyzed first, and then particular value activities that prove to be important are investigated in greater detail.
 
A final test for separating value activities is the behavior of competitors. Significant activities should be treated separately when a competitor performs them in a different way. Differences among competitors raise the possibility that an activity is the source of a relative cost advantage or disadvantage.