PRJ98: How to Calculate the Schedule and Cost Performance Index (209115)



The information in this article applies to:

  • Microsoft Project 98 for Windows

This article was previously published under Q209115

SUMMARY

Microsoft Project does not calculate the Schedule Performance Index (SPI) or the Cost Performance Index (CPI). This article contains a sample macro that calculates SPI and CPI for each task in a project.

NOTE: SPI is the ratio of work performed to work scheduled (BCWP/BCWS). CPI is the ratio of budgeted costs to actual costs (BCWP/ACWP).

MORE INFORMATION

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The following macro calculates the Schedule Performance Index (SPI) and the Cost Performance Index (CPI) for each task and places the results into Numeric fields. The SPI for each task is equal to BCWP/BCWS. The CPI for each task is equal to BCWP/ACWP.

To create this macro, follow these steps:
  1. On the Tools menu, point to Macro, and then click Macros.
  2. In the Macro name box, type CalcSPI_CPI, and then click Create to open the Visual Basic Editor.
  3. Create the macro by typing the following subroutine.
    Sub CalcSPI_CPI()
    Dim t As Task
    For Each t In ActiveProject.Tasks
      If Not t Is Nothing Then
        If t.BCWS <> 0 Then
            t.Number10 = t.BCWP / t.BCWS 'this calculates SPI
        End If
        If t.ACWP <> 0 Then
            t.Number11 = t.BCWP / t.ACWP 'this calculates CPI
        End If
      End If
    Next t
    End Sub
    						

    NOTE: This example uses the Number10 and Number11 fields. You can use any of the other numeric and alphanumeric fields available. You may also want to use the Format function to format your results.
  4. In the Visual Basic Editor, on the File menu, click Close And Return To Microsoft Project.
  5. In Microsoft Project, on the Tools menu, point to Macro, and then click Macros.
  6. In the list of macros, click CalcSPI_CPI. Click Run.
To view the results of the macro, insert the Number10 and Number11 field in a task table. To do this, follow these steps:

  1. On the Insert menu, click Column.
  2. In the Field name list, click Number10.
  3. Click OK.
  4. Repeat steps 1-3 for the Number11 field.

Modification Type:MajorLast Reviewed:6/23/2005
Keywords:kbhowto KB209115