Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
If Not IsNumeric(CStr(Target)) Then Exit Sub
Dim coef#
coef = 2.8357 'à ajuster par tâtonnement
Cancel = True
With Shapes.AddShape(msoShapeOval, 0, 0, 0, 0)
.Fill.ForeColor.RGB = vbYellow 'jaune
.Width = coef * Target
.Height = .Width
.Left = Target.Left + (Target.Width - .Width) / 2
.Top = Target.Top + (Target.Height - .Height) / 2
End With
End Sub