Only Showing the Maximum of Multiple Iterations

Mike has three cells (A1:A3) that show results of calculations. He needs a way to determine the maximum value that has ever appeared in any of these cells, and have that value stored in cell E5. He knows how to get the maximum out of the three, but when he recalculates the worksheet, if the values in A1:A3 are less than the maximum value in E5 (based on previous determinations of the maximum in A1:A3), then E5 should not change. In other words, E5 should only change if whatever is in A1:A3 is greater than what is in E5. Mike isn't sure how to perform such a calculation.

There are two ways you can solve this issue. The first is to create a simple formula that would be placed in cell E5:

=MAX(A1:A3,E5)

The MAX function examines the various values it references and then returns the maximum out of them—exactly what is wanted. However, since this formula is being placed in cell E5 and it also references E5, it will return an error. This is because the formula creates a circular reference. Excel can handle those, but you need to make a small configuration change to do it:

1. Choose Options from the Tools menu. Excel displays the Options dialog box.
2. Display the Calculation tab. (See Figure 1.)



Figure 1. The Calculation tab of the Options dialog box.

3. Make sure the Iteration check box is selected.
4. Click OK.

Now Excel will handle circular references, such as the simple formula you've put in cell E5.

The second approach is to use a macro to perform the calculation. This approach may be preferred because you may not want (for some reason) to enable circular references in your workbook. The following is actually an event handler, added to the code for the worksheet. (Easiest method: Right-click on the sheet tab, display the code window from the resulting Context menu, and add the macro to that code window.)

Private Sub Worksheet_Calculate()
    Dim dMax As Double
    dMax = Application.WorksheetFunction.Max(Range("A1:A3"))
    If dMax > Range("E5") Then
        Application.EnableEvents = False
        Range("E5") = dMax
        Application.EnableEvents = True
    End If
End Sub

The macro is triggered every time the worksheet is recalculated. It grabs the maximum of A1:A3 and compares it to what is in E5. Only if it is larger is that value then placed into E5.

ExcelTips is your source for cost-effective Microsoft Excel training. This tip (10915) applies to Microsoft Excel 97, 2000, 2002, and 2003. You can find a version of this tip for the ribbon interface of Excel (Excel 2007 and later) here: Only Showing the Maximum of Multiple Iterations.