ASP.NET Stackedbar chart markers - asp.net

Question

I am trying to add markers on my stacked bar chart programmatically and they do not seem to show up. In reality, I need to show a marker on the average of the datapoint but right now, I cannot even show a simple marker on the chart.
What am I doing wrong ?
Code:
Dim chart As New Chart
chart.ID = DtDistinct.Rows(I)("CourseSisID")
Dim chartareas As New ChartArea
chart.ChartAreas.Add(chartareas)
chart.Series.Clear()
chart.DataBindCrossTable(DtRecords.DefaultView, "Outcomescore", "ShortName", "RecordsPerGroup", "")
chart.ChartAreas(0).AxisY.Interval = 1
chart.ChartAreas(0).AxisY.Enabled = AxisEnabled.False
chart.Palette = ChartColorPalette.None
chart.PaletteCustomColors = New Color() {ColorTranslator.FromHtml("#DF5B59"), ColorTranslator.FromHtml("#E0D773 "), ColorTranslator.FromHtml("#8AAC53"), ColorTranslator.FromHtml("#6A843F")}
chart.ChartAreas(0).AxisX.MajorGrid.Enabled = False
chart.ChartAreas(0).AxisY.MajorGrid.Enabled = False
For Each cs As Series In chart.Series
cs.ChartType = SeriesChartType.StackedBar
cs.Points().FindMaxByValue.MarkerColor = Color.AliceBlue
cs.Points().FindMaxByValue.MarkerSize = 13
cs.Points().FindMaxByValue.MarkerStyle = MarkerStyle.Diamond
Next
pnlcharts.Controls.Add(chart)
Here is an image of what I am trying to do. I know that the above code will not give me the below image but I was trying to find a workaround with the above code, before I realized that markers cannot appear on bar charts.
I would like to see that striped line on the bar chart. The striped line should appear on the calculated average of the points.
So, an another way I could do was to use annotations since markers are not supported by stackedbar charts. I wrote the following code to add an annotation line, but it still does not give me the output I need only because I do not know how to do it for each Y value on the chart.
Here is my code:
Dim chart As New Chart
chart.ID = DtDistinct.Rows(I)("CourseSisID")
Dim chartareas As New ChartArea
chart.ChartAreas.Add(chartareas)
chart.DataBindCrossTable(DtRecords.DefaultView, "OutcomeScore", "ShortName", "RecordsPerGroup", "Label=RecordsPerGroup")
chart.Palette = ChartColorPalette.None
chart.PaletteCustomColors = New Color() {ColorTranslator.FromHtml("#DF5B59"), ColorTranslator.FromHtml("#E0D773 "), ColorTranslator.FromHtml("#8AAC53"), ColorTranslator.FromHtml("#6A843F")}
chart.ChartAreas(0).AxisX.MajorGrid.Enabled = False
chart.ChartAreas(0).AxisY.MajorGrid.Enabled = False
Dim charttitle As New Title
charttitle.Text = DtDistinct.Rows(I)("CourseSisID")
chart.Titles.Add(charttitle)
For Each cs As Series In chart.Series
cs.ChartType = SeriesChartType.StackedBar
Next
Dim ann1 As New VerticalLineAnnotation()
ann1.AxisX = chart.ChartAreas(0).AxisX
ann1.AxisY = chart.ChartAreas(0).AxisY
ann1.IsSizeAlwaysRelative = False
ann1.X = chart.DataManipulator.Statistics.Mean(chart.Series(0).Name)
ann1.IsInfinitive = True
ann1.ClipToChartArea = chart.ChartAreas(0).Name
ann1.LineColor = Color.Coral
ann1.LineWidth = 3
ann1.AnchorX = 1
ann1.AnchorY = 5
chart.Annotations.Add(ann1)
ann1.LineDashStyle = ChartDashStyle.Dash
pnlcharts.Controls.Add(chart)
Here is what I get with the above code:
Here is what I need : Notice how the strip line is at a different value for each bar.

Answer 1

Dim annotation2 As New LineAnnotation()
annotation2.IsSizeAlwaysRelative = False
annotation2.AxisX = chart.ChartAreas(0).AxisX
annotation2.AxisY = chart.ChartAreas(0).AxisY
annotation2.Height = 1
annotation2.Width = 0
annotation2.LineWidth = 1.5
annotation2.StartCap = LineAnchorCapStyle.None
annotation2.EndCap = LineAnchorCapStyle.None
annotation2.AnchorX = AvgVar
annotation2.ToolTip = "Average=" & AvgVar
Select Case row
Case 1
annotation2.AnchorY = 4.5
Case 2
annotation2.AnchorY = 3.5
Case 3
annotation2.AnchorY = 2.5
Case 4
annotation2.AnchorY = 1.5
Case 5
annotation2.AnchorY = 0.5
End Select
' <- your point
annotation2.LineColor = Color.Gray
annotation2.LineDashStyle = ChartDashStyle.Dash
' <- your color
chart.Annotations.Add(annotation2)