A
=ARRONDI(ABS(PREVISION(A2;DECALER(B3;0;0;$B$1;1);DECALER(A3;0;0;$B$1;1)));0)
=SI(LIGNE()>NB(A:A)-B$1+2;"";ARRONDI(ABS(PREVISION(A2;DECALER(B3;;;B$1);DECALER(A3;;;B$1)));0))
Sub Maximum()
Dim n&, maxi&, x$, nn&
Application.ScreenUpdating = False
For n = 3 To Application.Count([A:A])
Range("B1") = n
If Range("E1") > maxi Then maxi = Range("E1"): x = ""
If Range("E1") = maxi Then x = x & " - " & n: nn = n
Next
Range("B1") = nn
Range("F1") = "Maximum " & maxi & " pour B1 = " & Mid(x, 4)
End Sub