Project scheduling – Understanding % complete

Introduction

The concept of % complete appears to be pretty straightforward but it can also be confusing and misleading if not defined properly.

Consider  an activity that takes five days of effort to complete plus five elapsed days for approval by four stakeholders. What is the % complete when the work is finished and one stakeholder has approved?

  • If you assume that 100% represents five days of effort, then you can say that it is 100% complete (assuming no effort for approvals)
  • If you assume that 100% represents 10 days of duration, then you can say that it is 50% complete
  • If you assume that 100% represents four approvals then you can say that it is 25% complete

What is the correct answer? -It depends on which reference is used for 100%, and that is usually determined by who is asking the question, therefore a % complete statement should always be qualified on a report to avoid misunderstandings.

Treatment of % complete in Project

In Project there are three different % complete fields to choose from. You can update any of these fields directly by selecting a number between 0 and 100, with 0 meaning that the task has not started and 100% meaning that the task is complete.

% complete is the default field and refers to task duration.

  • When % complete of a task is changed, % work complete is also modified in line with the changes.
  • % complete is used to calculate task BCWP (Budget Cost of Work Performed) in earned value.
  • This field can be updated indirectly by updating the actual duration and/or remaining duration of the task. Sometimes this can lead to a decrease in the % complete when the remaining duration is increased. This changes the baseline against which earned value is being measured and is a problem that should be avoided.

% work complete is applied to resource allocations but can also be used at a task level.

  • Changing % work complete of individual resources changes the overall % work complete of the task in proportion to the individual changes.
  • Changing % of work completed of the task changes % work complete of each assigned resource in proportion to their allocation and also changes % complete of the task.
  • This field can be updated indirectly by entering actual work against the task or the assigned resources.
  • A task or milestone may not have resources allocated to it. In this case changing % work complete does not change % complete.

Physical % complete is always entered manually and can be used instead of % complete in earned value calculations.

  • This field is not affected by changes in the estimated total duration or work (the basis of 100%) allowing re-forecasting the task without affecting the project metrics.
  • It is also used when applying a standard to measure progress, such as the number of approvals in the example before.

Conclusion

Paraphrasing Mark Twain there is % complete, % work complete and Project

Each of these variables has a specific use and they should not be interchanged. Knowing which variable to use when creates a robust project schedule that increases the chances of completing the project successfully.