Variance at Completion (VAC) is a project cost metric that predicts whether the project will be over or under budget by the time it is completed. It is calculated using the formula:
VAC=BAC−EACVAC = BAC – EAC
Where:
- BAC (Budget at Completion) is the planned total project cost.
- EAC (Estimate at Completion) is the revised forecasted cost.
Interpreting VAC:
- Positive VAC → The project is expected to finish under budget.
- Negative VAC → The project is expected to exceed budget.
- Zero VAC → The project is expected to align exactly with budget.
This metric is critical for budget control and financial forecasting.
