Data Management Capabilities > Managing Projects > Classic Plans > Classic Plan Objects > Classic Milestones
  
Classic Milestones
A milestone can be either a date marker or a goal measurement, both of which are tracked as part of a classic project. A classic project can contain any number of both types of milestones. A goal measurement milestone usually has one or more deliverables associated with it. The duration is calculated based on the deliverables contained by the milestone. You cannot define a milestone as a parent of other milestones. Use the summary activity plan object to act as a parent of one or more milestones.
Date Marker Milestones
Milestones that serve as date markers usually have no duration associated with them. If you want the date marker milestone to represent a single date, enter 0 for the duration. You define the milestone as one of the two types in the way that you create the milestone. That is, the milestone type depends on the information that is specified during the creation of the milestone. For example, if you associate deliverables to the milestone, it becomes a goal measurement milestone.
If the project or program execution is set to automatically execute activities and deliver tasks, then all milestones act as date marker milestones since they automatically complete. Therefore, it is not possible to set a duration for milestones in this execution mode. If the milestone achievement must be manually verified, you should create an activity as a predecessor to the milestone to confirm that the milestone was actually achieved.
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It is usually most helpful to define dependencies, or predecessors, for date marker milestones. However, if you want the milestone to indicate a single date, you do not need to define predecessors.
Goal Measurement Milestones
A milestone is used to measure the goals of a project or program when it is associated with one or more deliverables. When creating this type of milestone, it is best not to define a duration since that information is calculated based on any associated deliverables. When deliverables are associated to a milestone, the finish date for the milestone is pushed out to the latest finish date of any associated deliverable. The percentage complete for the milestone will reflect the percentage complete of the associated deliverables. The milestone percentage complete is calculated using a simple average of the percentage complete values for the associated deliverables.
The milestone status is always calculated using a pessimistic approach. If any associated deliverable status is "red," then the milestone status is "red." If no deliverable status is "red" but one or more is "yellow," then the status of the associated milestone is "yellow." If the status of all its associated deliverables is "green," then the milestone status is also green."
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There is no Microsoft Project equivalent for the goal measurement milestone.