Microsoft Project allows you to represent the uncertainty of your schedule with estimated tasks. An estimated task is simply a task for which two or more of the following three data points are unknown: (a) start date, (b) finish date, or (c) duration.
Think of it this way. If we know the start date and finish date, then we know the duration, via arithmetic. Likewise, if we know the duration and the finish date, then we know the start date. But if we only know the start date – not the finish date or duration – then we don't really have any idea of how long the task is going to take. Thus it meets the definition of an estimated task.
- Project allows you to see which tasks are and are not estimated by providing the Estimated (Yes/No) field. Let's see it in action by starting with a new, blank project:
- Click the Add New Column heading and located Estimated in the field of values. That will display the Estimated column, currently blank since the rest of the document is blank as well.
- Now, let's define a task, simply entering its name under Task Name.
- Immediately after hitting Enter, we see four columns colored light blue. Duration, Start, and Finish are colored so we see we are missing data for those critical elements of a task. We also see that Estimated has been filled in with the value of Yes. Because we don't really know much of anything about our task, it begins its life in Estimated status. Now, what happens when we define the start date?
- Not much! Our task is still estimated, because we don't know the finish date and therefore don't know the duration either. OK, let’s say we're pretty sure the duration will be about a week.
- Just like that, the Estimated value changes from Yes to No. Now that Project knows the duration, it calculates the finish date to be a week from the start date, and we finally have the basic building blocks of a non-estimated task.
The Estimated field in Microsoft Project is useful for seeing the holes in your project plan as it evolves. Consider this more complex plan for a rocket launch:
- There are several tasks in this project plan where we are uncertain of the duration. This has been indicated with question marks following the duration, e.g. "42 days?". But looking at all these rows and columns, it's difficult to tell exactly where the uncertainty lies. By adding the Estimated column to our Project plan and then filtering to display only the Yes values...
- ...the picture becomes clearer:
Now we know where to focus team effort on defining and clarifying tasks.
Last Modified: December 14, 2020