Sub trans()
Dim tourne As Long
Dim mois As String
Dim Inter As String
For tourne = 3 To Range("L" & Rows.Count).End(xlUp).Row
Inter = Split(Range("l" & tourne), "-")(1)
mois = InStr(1, "__JanFebMarAprMayJunJulAugSepOctNovDec", Inter) / 3
Range("N" & tourne) = CDate(Replace(Range("L" & tourne), "-" & Inter & "-", "/" & mois & "/"))
Next tourne
End Sub