Sub Worksheet_Change(ByVal Target As Range)
If Target.Count > 1 Then Exit Sub
If Not Intersect(Target, Range("A1:A1000")) Is Nothing Then
If Target = "" Then
Cells(Target.Row, 1 + Target.Column) = ""
Else
Cells(Target.Row, 1 + Target.Column) = Date
End If
End If
End Sub