faire un graph avec données de plusieurs feuilles

Sub graph_pmo()
If TypeName(Selection) <> "ChartArea" Then Exit Sub
Dim X1 As Range
Dim X2 As Range
Dim Y1 As Range
Dim Y2 As Range
Dim C As Range
Dim A$
Dim B$
Dim SC As SeriesCollection
Set X1 = Application.InputBox(prompt:="Indiquez la plage des X1", Title:="Data X1", Type:=8)
Set X2 = Application.InputBox(prompt:="Indiquez la plage des X2", Title:="Data X2", Type:=8)
For Each C In X1
  A$ = A$ & C & ","
Next C
For Each C In X2
  A$ = A$ & C & ","
Next C
A$ = Mid(A$, 1, Len(A$) - 1)
Set Y1 = Application.InputBox(prompt:="Indiquez la plage des Y1", Title:="Data Y1", Type:=8)
Set Y2 = Application.InputBox(prompt:="Indiquez la plage des Y2", Title:="Data Y2", Type:=8)
For Each C In Y1
  B$ = B$ & C & ","
Next C
For Each C In Y2
  B$ = B$ & C & ","
Next C
B$ = Mid(B$, 1, Len(B$) - 1)
On Error Resume Next
Set SC = ActiveChart.SeriesCollection(1)
If Err <> 0 Then
  ActiveChart.SeriesCollection.NewSeries
  Err.Clear
End If
On Error GoTo 0
With ActiveChart.SeriesCollection(1)
  .Values = "={" & A$ & "}"
  .XValues = "={" & B$ & "}"
End With
End Sub