Cost-Behavior Patterns: Variable Costs and Fixed Costs
Costing systems record the cost of resources acquired, such as materials, labor, and equipment,
and track how those resources are used to produce and sell products or services.
Recording the costs of resources acquired and used allows managers to see how costs
behave. Consider two basic types of cost-behavior patterns found in many accounting systems.
A variable cost changes in total in proportion to changes in the related level of total
activity or volume. A fixed cost remains unchanged in total for a given time period,
despite wide changes in the related level of total activity or volume. Costs are defined as
variable or fixed with respect to a specific activity and for a given time period. The Global
Surveys of Company Practice on page 31 indicate that identifying a cost as variable or
fixed helps in making many management decisions. To illustrate these two basic types of
costs, consider costs at the Spartanburg, South Carolina, plant of BMW