temps passé sur un fichier

Dim T_Debut As Single
Dim T_Fin As Single
Dim T_Total As String

Private Sub Workbook_BeforeClose(Cancel As Boolean)

    T_Fin = Timer / 86400
    
    T_Total = Application.WorksheetFunction.Text(T_Fin - T_Debut, "[h]:mm:ss")
    
    MsgBox T_Total
    
End Sub

Private Sub Workbook_Open()

    T_Debut = Timer / 86400

End Sub

Dim T_Debut As Single
Dim T_Fin As Single

Private Sub Workbook_Open()
    
    'calcul du temps en fraction
    T_Debut = Timer / 86400

End Sub

Private Sub Workbook_BeforeClose(Cancel As Boolean)

   Fermeture
   
End Sub


Sub Fermeture()
    
    Dim Fe As Worksheet
    Dim L As Integer
    
    'la feuille doit s'appeler Temps Passé
    Set Fe = Worksheets("Temps Passé")
    
    'calcul du temps en fraction
    T_Fin = Timer / 86400
    
    With Fe
        
        'première ligne vide
        L = .Cells(.Rows.Count, 1).End(xlUp).Row + 1
        
        .Range("A" & L).Value = Date 'date du jour
        .Range("B" & L).Value = T_Debut 'ouverture du classeur
        .Range("C" & L).Value = T_Fin 'fermeture du classeur
        .Range("D" & L).Value = T_Fin - T_Debut 'delta (temps passé)
        .Range("D" & L).NumberFormat = "[h]:mm:ss" 'formatage [h]:mm:ss (plus parlant)
        
    End With
    
    TotalHeures
    
End Sub

Sub TotalHeures()

    Dim Fe As Worksheet
    Dim L As Integer
    Dim I As Integer
    Dim Total As Single
    
    'la feuille doit s'appeler Temps Passé
    Set Fe = Worksheets("Temps Passé")
    
    With Fe
    
        'dernière ligne non vide
        L = .Cells(.Rows.Count, 1).End(xlUp).Row
        
        'début du cumul
        .Range("E2").Value = .Range("D2").Value
        .Range("E2").NumberFormat = "[h]:mm:ss"
        
        'cumule
        For I = 3 To L
        
            .Range("E" & I).Value = .Range("E" & I - 1).Value + .Range("D" & I).Value
            .Range("E" & I).NumberFormat = "[h]:mm:ss"
       
        Next I
        

    End With
    
End Sub