calcul en mois et jours

Function diffDateSpe(d1 As Date, d2 As Date) As String
Dim m&, j&
  If CLng(d1) <= CLng(d2) Then
    If d1 > 60 Then                                'Parce que, chez Microsoft, il existe un 29/02/1900 !'
      d2 = d2 + 1                                  'Pour que    0 - 0 = 1                               '
      Do While DateSerial(Year(d1), Month(d1) + m + 1, Day(d1)) <= d2: m = m + 1: Loop      'Mois       '
      Do While DateSerial(Year(d1), Month(d1) + m, Day(d1) + 1) + j <= d2: j = j + 1: Loop  'Jours      '
        diffDateSpe = IIf(m, m & " mois ", "") & _
      IIf(j Or (m + j = 0), j & " jour" & IIf(j > 1, "s", ""), "")                          'Affichage  '
    End If
  End If
End Function