Moderator: Intaver Support
If during project execution, you continue to use the above process, where costs are calculated based on duration, resource allocation, and rates then you can continue. Problems occur if you mix methodologies such that you calculate future costs based on the above formula, but you manually enter actuals for work in for tasks or resources. This causes calculations to become decoupled with the forecast method. The reason for this is if tasks that are partially completed, there are now 2 sources of Actual cost data: calculated work based on duration, % complete, and resource allocation; and Actual Work entered for a Tasks or a Resource. This can become even more complicated when resources are assigned to n>1 activity.
If this is the case, you have two options.
One, create a copy of your schedule so that you one that can be used for running risk analysis that uses the Fixed Units, % Complete, and Resource allocation to calculate Actuals. In most cases, this will be adequate as the point of running the analysis is not to calculate where you are, but forecast what the implications of current progress means to meeting schedule and budget.
Two, you can use manually entered Work, but you will need to remove any uncertainty from the Task Duration by setting the Task types for incomplete tasks to Fixed Duration.
From our standpoint, there are trade offs that need to be balanced from both approaches based on how your organization wants to manage their projects and the resources that are available to run your risk analysis.
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