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Activity-Based Costing
Modeling with activity-based costing
Multiple Resources model
Multiple Resources model
In the example model, the cost accumulator is initially batched with 2 of Resource A and 2 of Resource C. When multiple resources are batched with a cost accumulator, they may be released all at once (as with Resource A), released incrementally (as with Resource C), or remain with the cost accumulator. Whenever a resource is batched or released, the cost array of the cost accumulator is updated to reflect the current number of resources in use. (The cost array is described in “Combining resources with cost accumulators” on page 290.)
There are three things to remember when batching resource items with cost accumulators:
1) Aresourcewillbereleasedfromtheoutputconnectorthatcorrespondstotheinputconnec- tor originally used to batch it to the cost accumulator. For example, if the resource entered the Batch block through the “ItemsIn(2)” connector, it will be released through the Unbatch block’s “ItemsOut(2)” connector.
☞ As in the Multiple Resources model, this could mean that one or more of the Unbatch block’s outputs will be unconnected and you will need to define that there will be zero items output through that connector.
2) Ifanitemissimultaneouslybatchedwithdifferenttypesofresources,youmustusediffer- ent connectors for each resource type when creating the batch. In the Multiple Resources model above, Resource A uses connector “ItemsIn” and Resource C uses connector “Item- sIn(2)”.
3) WhenperformingABC,youarelimitedtotwodifferenttypesofresourceitemsbatched with a cost accumulator item at one time. This limitation is not true, however, when model- ing resources using the resource pool blocks, as you will see below.
Cost accumulators and the resource pool blocks
As described in “Resource Pool method” on page 224, as cost accumulating items pass through a Queue block in Resource Pool mode, resources are allocated to the items. When this hap- pens, the cost rate of the resource pool unit is automatically stored with the cost accumulator and used in any subsequent cost calculations.
Discrete Event

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