Option Explicit
Sub gpeFormatDate()
Dim Rng As Range, Cls As Range
For Each Cls In Range([A4], [A65500].End(xlUp))
If Cls.Value = Cls.Offset(-1).Value Then
Cls.NumberFormat = "''"
Else
Cls.NumberFormat = "dd/mm"
End If
Next Cls
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
If Not Application.Intersect(Target, Range([A4], [A65500].End(xlUp))) Is Nothing Then
Target.NumberFormat = "dd/mm"
End If
End Sub