Option Explicit
Sub EssAi()
Dim DerLig As Long
DerLig = Feuil1.Range("C" & Rows.Count).End(xlUp).Row
Range("A3").FormulaLocal = "=SOMME(C8:C" & DerLig & ")" ': Range("A3") = Range("A3").Value
Range("A4").FormulaLocal = "=SOMME(D8:D" & DerLig & ")" ': Range("A4") = Range("A4").Value
End Sub