In the Workflow Builder, there is an option to set a 'Progress Type'. Progress Types visually display a project's progress.

This type calculates project progress based on its current position.  For example, if you have 4 statuses in a workflow, when a project is in status 3 the progress bar will show as 67% complete.
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This type lets use set the project progress for each status directly in the workflow builder.  For example, if you think the majority of the work happens after status #2, go ahead and set the project to being 95% complete by status #3.  It's up to you!
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This type lets users set the project progress directly on the 'Edit Project' page.
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