Here is yet another way of creating graphics in Excel - using VBA macro, like this one:
Sub DrawDefShape()
'Draws any defined shape representing Bézier curves
Dim x As Integer, y As Integer
Dim pt(1 To 7, 1 To 2) As Single
Dim rng As Range
Set rng = Sheets("Data").Range("A2:B8")
'Fill array of control point coordinates with values
For x = 1 To 7
For y = 1 To 2
pt(x, y) = rng.Cells(x, y).Value
Next y
Next x
Set myDoc = Worksheets("Data")
myDoc.Shapes.AddCurve SafeArrayOfPoints:=pt
Range("A10").Select
'Display the whole 2D array in MsgBox
For i = 1 To UBound(pt)
dPts = dPts & pt(i, 1) & " " & pt(i, 2) & vbNewLine
Next i
MsgBox dPts
End Sub
Before going into the details of the macro structure and its use, let's look at some examples of curves and shapes you can easily create with it. Here they are: