Automatiser des formules en vba

Sub UpgradeParValeur()
Dim lastLig&
Dim var
Dim i&
Dim T()
Dim borne&
lastLig& = [a65536].End(xlUp).Row
var = Range(Cells(1, 1), Cells(lastLig&, 19))
ReDim T(2 To lastLig&, 1 To 2)
borne& = CLng(var(1, 19))
For i& = 2 To lastLig&
  If var(i&, 15) = "MN" Then
    T(i&, 2) = borne& - (CLng(var(i&, 7)) + 18)
  Else
    T(i&, 2) = borne& - (CLng(var(i&, 7)) + 38)
  End If
  If T(i&, 2) <= 0 Then
    T(i&, 1) = "OK"
  Else
    T(i&, 1) = "Retard"
  End If
Next i&
Range(Cells(2, 17), Cells(lastLig&, 18)) = T
End Sub