# 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. Display the Excel Options dialog box. (In Excel 2007 click the Office button and then click Excel Options. In Excel 2010 display the File tab of the ribbon and then click Options.)
2. Click Formulas at the left side of the dialog box. (See Figure 1.)
3. Figure 1. The formulas options in the Excel Options dialog box.

***Insert Figure 4 ? S01816.tif

4. Make sure the Enable Iterative Calculation check box is selected.
5. 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.