                              const portfolio = portfolioData[context.dataIndex];
                                    const label = `Value: $${context.raw.toFixed(2)}`;
                                    const gainLoss = `Gain/Loss: $${portfolio.gain_loss.toFixed(2)} (${portfolio.gain_loss_percentage.toFixed(2)}%)`;
                                    return [label, gainLoss];
                                }
                            }
                        }
                    }
                }
 