Further to Dave Peterson's reply, if you want to only note this one
cell value (A1) if it has actually changed during a calculation pass,
you could use:

Private Sub Worksheet_Calculate()
If Me.Range("A1").Value< Worksheets("Sheet2") _
.Range("A65536").End(xlUp).Value Then
Application.EnableEvents = False
Me.Range("a1").Copy _
Destination:=Worksheets("Sheet2") _
.Range("A65536").End(xlUp).Offset(1)
Application.EnableEvents = True
End If
End Sub


Bill Manville
MVP - Microsoft Excel, Oxford, England
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