Public OldValue As Integer
Private Sub Workbook_Open()
OldValue = Sheets('Feuil1').Range('B2')
End Sub
Dim InChange As Boolean
'-----------------------------------
Private Sub Worksheet_Change(ByVal Target As Excel.Range)
If Not InChange Then
InChange = True
If Target.Address = '$B$2' Then
If IsEmpty(Target.Value) Then
OldValue = 0
Else
Target = Target + OldValue
OldValue = Target
End If
End If
InChange = False
End If
End Sub