Schleifenproblem

Sub Test()
' Histogram erstellen
Zeile = 2
Do Until Cells(Zeile + 1, 13) = ""
Testname = Cells(Zeile, 13)
Start = "$F$" & Zeile
Do Until Cells(Zeile, 13) <> Testname
Zeile = Zeile + 1
Loop
Ende = "$F$" & Zeile - 1
Position = Zeile - 10
Application.Run "ATPVBAEN.XLA!Histogram", ActiveSheet.Range(Start & ":" & Ende), _
ActiveSheet.Range("$S$" & Position), , False, False, False, False
dstart = "S" & Position
kzeile = Position
dende = "T" & 20
Cells(2, 14) = dstart
Cells(2, 15) = dende
Range(dstart & ":" & dende).Select
Charts.Add
ActiveChart.ChartType = xlColumnClustered
ActiveChart.SetSourceData Source:=Sheets("Tabelle1").Range(dstart & ":" & dende), _
PlotBy:=xlColumns
ActiveChart.Location Where:=xlLocationAsObject, Name:="Tabelle1"
With ActiveChart
.HasTitle = True
.ChartTitle.Characters.Text = "titel"
.Axes(xlCategory, xlPrimary).HasTitle = False
.Axes(xlValue, xlPrimary).HasTitle = False
End With
ActiveChart.HasLegend = False
Loop
End Sub