Sub test_II()
Dim LG&, CL&, i&, PlG As Range
LG = Cells(Rows.Count, 1).End(3).Row
CL = Cells(5, 2).End(xlToRight).Column
On Error Resume Next
For i = 2 To CL
Set PlG = Cells(5, i).Resize(LG - 4)
PlG.SpecialCells(2, 2).Value = Application.Average(PlG)
Set PlG = Nothing
Next
End Sub