In a time-driven ABC system, updates are usually required when there are changes in production volume, changes in variable costs, and changes in market demand since these factors influence the cost of production and resource utilization.
Updates to a time-driven Activity-Based Costing (ABC) system could be triggered by changes that affect the cost of production. Among the options provided, the most applicable triggers would include changes in production volume, changes in variable costs, and changes in market demand. These elements directly impact the resources used by a company and the overall efficiency of the processes, which would therefore require updates in the ABC system to accurately allocate overhead costs to products or services based on the actual consumption of resources.
Changes in the number of producers, change in Government policy, and a change in producers price expectations may not directly lead to updates in a time-driven ABC system but can impact market conditions which in turn, could affect production variables prompting a review of the system.