This code
Sub CreateChart()'PURPOSE: Create a chart (chart dimensions are required)

Dim rng As Range
Dim cht As ChartObject
Dim i As Long

i = Cells(2, "P").Value
 'Debug.Print "P2 =", i

'Your data range for the chart
  Set rng = ActiveSheet.Range("P4:U" & i)

'Create a chart
  Set cht = ActiveSheet.ChartObjects.Add( _
    Left:=30, _
    Width:=580, _
    Top:=250, _

'Give chart some data
  cht.Chart.SetSourceData Source:=rng
'Determine the chart type
  cht.Chart.ChartType = xlXYScatterLines
  cht.Chart.HasTitle = True
  cht.Chart.ChartTitle.Text = Cells(2, 4).Value & "-Site Model of Population"

End Sub
produces this chart Chart.3g.1.jpg

I would like it colored to look like Chart.3g.jpg Note, the two charts use different data.