The %complete is based on duration and not the work specifically, so you need to ensure that both duration and work are consistent, since the %complete at the subtask level is usually done from the work load.

TTFN

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I understand % complete is based on duration and the summary should roll up accordingly. I have zeroed out the project percentage and re-entered based on subtask completion. The subtasks contain a mixture of tasks with durations as well as milestones which I've set to 100%.

All the subtasks have durations that end before or up to 5/20 and my project has a completion date of 9/26. Once I set the subtasks to 100% (for the most part), the overall summary task bar is now showing 71% complete through 7/25.

So I'm not clear on how the summary task bar calculates the overall percent complete for the project. As a note, I have only provided percent complete for roughly the first 70 lines of a 230 line schedule.
 

I don't necessarily see that there's a problem.  If, as is typical in some projects, your workload is front-loaded, then you might well be 71% complete at the midpoint of the total project duration.  

The summary %complete is the ratio of the sum of the durations of the completed tasks divided by the sum of all the durations.   

TTFN

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I agree that if the bulk of the workload is front-loaded, it may show this, but that's not the case with my project. Additionally, I'm not clear on how the percent complete can exceed today's date.

If I update the percent complete on all subtasks completed to date, the summary task shows complete through 9/9/08 (91%) which is obviously not accurate since I have a little over 2 months left of tasking.

Summary tasks are subtotals and subtitles to help organize work.  They should never have resources assigned nor should they be tracked.  Summary tasks will only be correct in percent complete when there is 0% completed or 100% completed.  Keep in mind they are totaling the work and duration of the detail tasks below in the WBS. If you are tracking tasks and re-scheduling uncompleted work, you should let the tasks drive the project, not the summary tasks. In the area of best practices of using MS Project, tracking summary tasks is not recommended.

Ellen Lehnert, PMP, MCT
www.lehnertcs.com   

If the summary task %complete is inaccurate, then MSP shouldn't display anything there.

TTFN

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