Sub Macro5()
Dim a(1 To 30, 1 To 2)
Dim Temp As Double
'Remplissage du tableau
j = 2: G = 6
For Z = 1 To 2
For i = 1 To 30
a(i, Z) = Sheets("Feuil1").Cells(i + 8, j + Z).Value
Next i
MsgBox Application.Average(Application.Index(a, , Z))
Next Z
End Sub