Incorrect Calculation of Earned Values for Summary Tasks (75051)


The information in this article applies to:

  • Microsoft Project for Windows 1.0
  • Microsoft Project for Windows 4.0
  • Microsoft Project for Windows 95 4.1
  • Microsoft Project for the Macintosh 1.1
  • Microsoft Project for the Macintosh 4.0
This article was previously published under Q75051

SUMMARY

Microsoft Project does not correctly calculate either the Budgeted Cost of Work Performed (BCWS) or Budgeted Cost of Work Scheduled (BCWP) values for Summary tasks.

MORE INFORMATION

Project calculates the BCWP, or the "earned value" of the work performed, on an individual task using the following formula: 
   BCWP = [% Complete] x [Planned Cost]


The Planned Cost is also known as Budget at Completion (BAC).

Similarly, the BCWS, or the "planned earned value," for an individual task is calculated as follows: 
   BCWS = [Planned % Complete] x [Planned Cost]


The planned percent complete is based on today's date and the task's Planned Start and Planned Finish dates. The planned percent complete is only calculated internally by Project; it is not available as a field that can be added to a task table.

The BCWS and BCWP values for a Summary task are computed in exactly the same way: 
   Summary BCWS = [Summary % Complete] x [Summary Planned Cost]
				
   Summary BCWP = [Summary % Complete] x [Summary Planned Cost]


However, this calculation is incorrect. The correct values result from the following formulas: 
   Summary BCWP = Sum of all BCWP's from the sub-tasks
				
   Summary BCWS = Sum of all BCWS's from the sub-tasks

WORKAROUND

One way to work around this limitation is to export the earned value information from the non-summary tasks to another application, such as Excel, and perform the summarization there.

If you are using Microsoft Project version 4.0, you can create a Visual Applications Edition macro that will rollup the BCWP and BCWS values from the sub-tasks to the summary level.

STATUS

Microsoft has confirmed this to be a problem in the products listed at the beginning of this article. We are researching this problem and will post additional information here in the Microsoft Knowledge Base as it becomes available. This is not a problem in Microsoft Project version 3.0.
Modification Type:MajorLast Reviewed:11/25/2003
Keywords:kbprb kbusage KB75051
©2003 Microsoft Corporation. All rights reserved.