Sub Итоги()

Set s = Columns("A").Find("Итого:", , xlValues, xlWhole, , , False)
nStartRow = 6
    
If Not s Is Nothing Then
    firstAddress = s.Address
    Do
        Range("F" & s.Row).Formula = "=Sum(F" & nStartRow & ":F" & s.Row - 1 & ")"
        nStartRow = s.Row + 1
        Set s = Columns("A").FindNext(s)
    Loop While Not s Is Nothing And s.Address <> firstAddress
End If

End Sub