Salut Saml,
En VBA : tu modifies le texte en [E2]...
Private Sub Worksheet_Change(ByVal Target As Range)
'
Dim tSplit, iTot%
'
If Not Intersect(Target, Range("E2")) Is Nothing Then
[F2] = ""
If Target <> "" Then
tSplit = Split(Target, " ")
For x = 0 To UBound(tSplit)
Set rCel = Columns(1).Find(what:=WorksheetFunction.Proper(tSplit(x)), lookat:=xlWhole, LookIn:=xlValues)
If Not rCel Is Nothing Then iTot = iTot + CInt(rCel.Offset(0, 1))
Next
[F2] = iTot
End If
End If
'
End Sub
A+