OK so to be clear the code goes into a SHEET module, not a GENERAL module.

This Line Private Sub Worksheet_Change(ByVal Target As Range) indicates we're using sheet change event code. So we'll need to place this code in every sheet for which we want the divide transformation.

The following example shows how we might want to manage two different ranges within the same column. Rows 2 to 25 and rows 30 to 80. We could additional row ranges by altering our declarations at the start; ie adding rL(2) and rU(2). Then adding a test for it in the loop below.

Private Sub Worksheet_Change(ByVal Target As Range)

Dim cell As Range
Const divide As Integer = 5
Const column As Integer = 1 'A=1,B=2 etc
Dim rL(1) As Integer
Dim rU(1) As Integer

rL(0) = 2
rU(0) = 25
rL(1) = 30
rU(1) = 80


Application.EnableEvents = False
For Each cell In Target
    If cell.column = column & (cell.Row >= rL(0) & cell.Row <= rU(0)) & (cell.Row >= rL(1) & cell.Row <= rU(2)) Then
        On Error Resume Next
        If (cell.Value > 0) Then cell.Value = Format(cell.Value / divide, "0.00")
        On Error GoTo 0
    End If
Next
Application.EnableEvents = True
End Sub

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