Générer valeurs aléatoires entre bornes dont la somme déterminée

Const plage = "A1:A20"
Const total = 10000
Const mini = 100
Const maxi = 1000

Public Sub tirageR()
Dim n As Long, tot As Long, a As Long, k As Long, d As Long, T
If Range(plage).Columns.Count > 1 Then Exit Sub
n = Range(plage).Cells.Count
ReDim T(1 To n)
tot = 0
For k = 1 To n
  a = mini + Int((maxi - mini + 1) * Rnd)
  tot = tot + a
  T(k) = a
Next k
If tot < total Then
  d = total - tot
  For k = 1 To d
    a = 1 + Int(n * Rnd)
    If T(a) < maxi Then
      T(a) = T(a) + 1
    Else
      k = k - 1
    End If
  Next k
ElseIf tot > total Then
  d = tot - total
  For k = 1 To d
    a = 1 + Int(n * Rnd)
    If T(a) > mini Then
      T(a) = T(a) - 1
    Else
      k = k - 1
    End If
  Next k
End If
Range(plage) = Application.Transpose(T)
End Sub

 Dim c As Range
For Each c In Range("A1:B50")'a adapter à la plage
c.Value = Int(Rnd * 99) + c
Next c

 Dim c As Range
For Each c In Range("A1:B50")
c.Value = Int(Rnd * 99)
Next c

If tot < total Then
  d = total - tot
  For k = 1 To d
    a = 1 + Int(n * Rnd)
    If Range(plage).Cells(a, 1) < maxi Then
      Range(plage).Cells(a, 1) = Range(plage).Cells(a, 1) + 1
    Else
      k = k - 1
    End If
  Next