Не вычисляется комиссия

private readonly CommissionManager _commissionManager = new CommissionManager();

readonly CommissionRule _commissionRule = new CommissionRule { Type = CommissionTypes.PerTradeVolume, Value = new Unit(0.09m) };

_commissionManager.Rules.Add(_commissionRule);

private void OnStrategyPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            this.GuiAsync(() =>
                {
                    TbStartedTime.Text = _levelSarStrategy.StartedTime.ToString(CultureInfo.InvariantCulture);
                    TbWorkingTime.Text = _levelSarStrategy.TotalWorkingTime.ToString();
                    TbSlippage.Text = _levelSarStrategy.Slippage.ToString(CultureInfo.InvariantCulture);
                    TbPosition.Text = _levelSarStrategy.Position.ToString(CultureInfo.InvariantCulture);
                    TbPnL.Text = _levelSarStrategy.PnL.ToString(CultureInfo.InvariantCulture);
                    TbLatency.Text = _levelSarStrategy.Latency.ToString();
                    TbCommision.Text = _levelSarStrategy.Commission.ToString(CultureInfo.InvariantCulture);
                });
        }