Format label compte à rebour

Public Marche As Boolean

Sub Ellipse1_Clic()
Dim fin As Double
marche = Not marche
fin = Now + ([macell ] * TimeValue("00:00:01"))
With ActiveSheet.Label21
        While fin >= Now And marche = True
                .ForeColor = vbGreen
                '.Caption = Format(fin - Now, "mm:ss") ' ????? affichage 12:xx
                .Caption = Minute(fin - Now) & ":" & Format(Second(fin - Now), "00")
                DoEvents
        Wend
        .ForeColor = vbRed
End With
End Sub

Sub Compte_à_rebours()
Static arret As Boolean
Dim i&, t#
If arret Then End
arret = True
For i = ActiveCell.Offset(0, 3) To 0 Step -1
  Label1 = Int(i / 60) & ":" & Format(i - 60 * Int(i / 60), "00")
  t = Timer + 1 'temporisation 1 seconde
  While Timer < t: DoEvents: Wend
Next
arret = False
End Sub

Sub Compte_à_rebours()
Static marche As Boolean
Dim i&, t#
If marche Then marche = False: Exit Sub
marche = True
For i = ActiveCell.Offset(0, 3) To 0 Step -1
  Label1 = Int(i / 60) & ":" & Format(i - 60 * Int(i / 60), "00")
  t = Timer + 1 'temporisation 1 seconde
  While Timer < t: DoEvents: Wend
  If Not marche Then Exit For
Next
marche = False
End Sub