Option Explicit
Sub Test()
Dim i As Long
With ThisWorkbook
For i = 3 To 4
Call DiagrammErstellen(.Worksheets(i))
Next
End With
End Sub
Function DiagrammErstellen(Worksheet As Excel.Worksheet) As Excel.Chart
Dim objChart As Excel.Chart
With Worksheet
If .ChartObjects.Count > 0 Then
Set objChart = .ChartObjects(1).Chart
Else
Set objChart = .Shapes.AddChart2().Chart
End If
Do While objChart.SeriesCollection.Count > 0
Call objChart.SeriesCollection(1).Delete
Loop
With .Range("A9")
objChart.ChartType = xlLine
Call objChart.SetSourceData( _
Source:=.Parent.Range(.End(xlDown), .End(xlToRight)), _
PlotBy:=xlColumns)
End With
End With
Set DiagrammErstellen = objChart
End Function