Sub test()
Cells.Replace What:=",", Replacement:=".", LookAt:=xlPart, SearchOrder _
:=xlByRows, MatchCase:=False, SearchFormat:=False, ReplaceFormat:=False
With Application
.UseSystemSeparators = True
End With
Dim LastCell As Range: Set LastCell = Range("B65536").End(xlUp).Offset(1)
LastCell.FormulaR1C1 = "=SUM(R1C:R[-1]C)"
LastCell.AutoFill LastCell.Resize(, 2)
LastCell.EntireRow.Cells(1) = "Èòîã:"
End Sub