Cost Proportionality
Use
This measurement technique is suitable for work packages where costs and services have a constant relationship.
Prerequisites
Costs must have been planned in the object, or actual costs posted to it, by period.
The system does not take account of costs from hierarchy planning in the WBS element.
Features
The system determines the percentage of completion (POC) for a period from the ratio of planned or actual costs to the overall planned costs. The system determines the planned or actual POC as follows:
BCWS = Planned costs/overall costs * 100
Actual EV = Actual costs/overall costs * 100
The planned costs are the cumulative planned costs up to the time of the calculation. The overall planned costs are the cumulative planned costs over the duration of the work package. You use the progress version to stipulate which cost plan the system uses.
Example
A work package has overall costs of $100,000.
The table shows how the POC is determined with reference to the overall costs.
Period |
1 |
2 |
3 |
Planned costs |
10,000 |
50,000 |
100,000 |
Planned POC |
10% |
50% |
100% |
Actual costs |
5,000 |
30,000 |
90,000 |
Actual POC |
5% |
30% |
90% |