How to Calculate Portfolio Weights with Beta and Expected Return

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Portfolio Weight Calculator: Beta & Expected Return

Understand and optimize your investment portfolio by calculating the optimal weights for assets based on their expected returns and risk (Beta). This tool helps you make informed decisions for a balanced and potentially more profitable portfolio.

Interactive Portfolio Weight Calculator

Enter a descriptive name for the first asset.
Enter the projected annual return percentage for Asset A.
Enter the Beta value for Asset A (e.g., 1.0 means market-like volatility).
Enter a descriptive name for the second asset.
Enter the projected annual return percentage for Asset B.
Enter the Beta value for Asset B (e.g., 0.8 means less volatile than the market).
Enter the projected annual return for the overall market.

Calculation Results

Optimal Portfolio Weight for [Asset Name]: N/A
Asset 1 Weight: N/A
Asset 2 Weight: N/A
Portfolio Expected Return: N/A
Portfolio Beta: N/A
Calculations based on optimizing weights to equalize the Sharpe Ratio component for each asset. Simplified representation often leads to approximating weights for risk parity or based on expected returns relative to risk. For a precise, robust optimization (like Markowitz), more complex inputs (covariances) are needed. This calculator provides a simplified view.

Asset Allocation Comparison

Visualizing the proposed weights for Asset 1 and Asset 2.

Key Input Parameters
Asset Expected Return (%) Beta
Asset A 10.0 1.2
Asset B 8.0 0.8
Market 10.0 1.0 (Assumed)

What is Portfolio Weighting with Beta and Expected Return?

Understanding how to calculate portfolio weights using metrics like Beta and Expected Return is fundamental to modern portfolio theory and effective investment management. Portfolio weighting refers to the process of determining the proportion of your total investment capital that should be allocated to each individual asset within your portfolio. The goal is to construct a portfolio that aligns with your risk tolerance, return objectives, and overall financial goals.

Expected Return is the anticipated profit or loss on an investment, typically expressed as a percentage of the initial investment. It's a crucial input because it quantifies the potential upside of an asset. Investors naturally gravitate towards assets with higher expected returns, assuming all other factors are equal.

Beta, on the other hand, measures an asset's volatility or systematic risk in relation to the overall market. A Beta of 1.0 indicates that the asset's price tends to move with the market. A Beta greater than 1.0 suggests higher volatility than the market, while a Beta less than 1.0 indicates lower volatility. Beta helps investors understand how much risk an asset adds to a diversified portfolio.

By combining these two metrics, investors can attempt to build portfolios that offer a desirable balance between potential returns and acceptable risk. It's a more sophisticated approach than simply picking assets based on one factor alone.

Who Should Use This Approach?

This methodology is beneficial for a wide range of investors, including:

  • Long-term investors: Seeking to optimize their asset allocation for growth over extended periods.
  • Risk-averse investors: Aiming to manage portfolio volatility by incorporating assets with lower Betas or adjusting weights accordingly.
  • Growth-oriented investors: Looking to maximize returns by identifying assets with high expected returns, while still being mindful of risk.
  • Financial advisors and portfolio managers: Utilizing quantitative methods to construct and manage client portfolios.

Common Misconceptions

Several misconceptions surround portfolio weighting:

  • "Higher Beta is always bad": While higher Beta implies higher volatility, it can also lead to higher returns during market upswings. The key is to manage the overall portfolio Beta.
  • "Expected Return is a guarantee": Expected return is a projection, not a certainty. Actual returns can differ significantly due to unforeseen market events and economic conditions.
  • "This single calculation is the final answer": Portfolio construction is dynamic. Factors like correlation between assets, investment horizon, and individual financial circumstances also play vital roles. This calculator offers a simplified perspective.
  • "Equal weights are always optimal": Unless assets have identical risk and return profiles, equal weighting is rarely the most efficient allocation.

Portfolio Weighting Formula and Mathematical Explanation

Calculating optimal portfolio weights based solely on Beta and Expected Return is a simplification of more robust portfolio optimization models like Markowitz's Modern Portfolio Theory (MPT). MPT requires inputs like expected returns, volatilities (standard deviations), and correlations between all assets.

However, a common heuristic or simplified approach often aims to balance risk and return. One way to conceptualize this is by aiming for a certain risk profile or return target. Without delving into complex quadratic programming (used in MPT), we can demonstrate a simplified approach that might inform allocation. A very basic approach might consider the ratio of expected returns to Beta, or try to equalize some risk-adjusted return metric.

A more practical approach for this calculator, without requiring full covariance matrices, is to use inputs that help in understanding contribution to portfolio risk and return. The formulas used in this calculator are designed to provide a conceptual understanding and a potential starting point.

Conceptual Calculation Approach:

The calculator aims to determine weights (w1, w2) such that the portfolio's characteristics are balanced. A simplified objective might be to achieve a portfolio Beta that is a weighted average of the asset Betas, and a portfolio Expected Return that is a weighted average of the asset Expected Returns.

Portfolio Expected Return (Rp) = w1 * E(R1) + w2 * E(R2)
Portfolio Beta (βp) = w1 * β1 + w2 * β2

Where:

  • w1, w2 are the weights of Asset 1 and Asset 2, respectively (w1 + w2 = 1).
  • E(R1), E(R2) are the expected annual returns of Asset 1 and Asset 2.
  • β1, β2 are the Betas of Asset 1 and Asset 2.

To find "optimal" weights without a full MPT framework (which would minimize variance for a given return, or maximize return for a given variance), we often use heuristics. A common heuristic might involve trying to equalize the risk contribution or adjust weights based on the relative attractiveness of risk-adjusted returns.

For instance, if we want to achieve a target portfolio Beta, we can solve for weights. Or, we might adjust weights based on the ratio of Expected Return to Beta.

The specific calculation implemented aims to provide a *suggested* allocation based on relative expected returns and Betas, acknowledging that a true optimization requires more data. The primary result highlights one asset's suggested weight.

Variables and Their Meanings:

Variable Meaning Unit Typical Range
w1, w2 Weight of Asset 1, Weight of Asset 2 Proportion (0 to 1) 0 to 1
E(R1), E(R2) Expected Annual Return of Asset 1, Asset 2 Percentage (%) -10% to 50%+ (highly variable)
β1, β2 Beta of Asset 1, Asset 2 Ratio (relative to market) Typically 0.5 to 2.0 (can be outside this range)
Rp Portfolio Expected Annual Return Percentage (%) Range depends on asset E(R) and weights
βp Portfolio Beta Ratio (relative to market) Range depends on asset Beta and weights
E(Rm) Market Expected Annual Return Percentage (%) Historical average ~7-10%

Practical Examples (Real-World Use Cases)

Example 1: Growth-Oriented Investor with Tech vs. Utility Stocks

An investor is considering two assets for their portfolio: a technology growth stock (Asset A) and a utility stock (Asset B).

  • Asset A (Tech Stock): High Expected Return (15%), High Beta (1.5)
  • Asset B (Utility Stock): Moderate Expected Return (7%), Low Beta (0.6)
  • Market Expected Return: 10%

Inputs for Calculator:

Asset 1 Name: Tech Growth Stock
Asset 1 Expected Return: 15%
Asset 1 Beta: 1.5

Asset 2 Name: Utility Stock
Asset 2 Expected Return: 7%
Asset 2 Beta: 0.6

Market Expected Return: 10%
                

Calculator Output (Illustrative):

The calculator might suggest weights like:

  • Asset 1 (Tech Stock) Weight: 60%
  • Asset 2 (Utility Stock) Weight: 40%
  • Portfolio Expected Return: (0.60 * 15%) + (0.40 * 7%) = 9.0% + 2.8% = 11.8%
  • Portfolio Beta: (0.60 * 1.5) + (0.40 * 0.6) = 0.90 + 0.24 = 1.14

Financial Interpretation: In this scenario, the investor is willing to accept a higher portfolio Beta (1.14, slightly more volatile than the market) to achieve a higher expected return (11.8%) compared to the market (10%). The weighting leans towards the higher-returning tech stock, acknowledging its higher risk. This allocation might suit an investor with a higher risk tolerance and a longer time horizon.

Example 2: Conservative Investor Balancing Index Fund and Bonds

A more conservative investor wants to balance a broad market index fund (Asset A) with a corporate bond fund (Asset B).

  • Asset A (Index Fund): Moderate Expected Return (10%), Market Beta (1.0)
  • Asset B (Bond Fund): Lower Expected Return (4%), Low Beta (0.2)
  • Market Expected Return: 10%

Inputs for Calculator:

Asset 1 Name: Market Index Fund
Asset 1 Expected Return: 10%
Asset 1 Beta: 1.0

Asset 2 Name: Corporate Bond Fund
Asset 2 Expected Return: 4%
Asset 2 Beta: 0.2

Market Expected Return: 10%
                

Calculator Output (Illustrative):

The calculator might suggest weights like:

  • Asset 1 (Index Fund) Weight: 50%
  • Asset 2 (Bond Fund) Weight: 50%
  • Portfolio Expected Return: (0.50 * 10%) + (0.50 * 4%) = 5.0% + 2.0% = 7.0%
  • Portfolio Beta: (0.50 * 1.0) + (0.50 * 0.2) = 0.50 + 0.10 = 0.60

Financial Interpretation: Here, the investor prioritizes capital preservation and lower volatility. The resulting portfolio Beta is significantly lower than the market (0.60), indicating reduced sensitivity to market movements. The expected return is also lower (7.0%), reflecting the trade-off for reduced risk. This allocation suits an investor with a low risk tolerance or a shorter investment horizon.

How to Use This Portfolio Weight Calculator

This calculator provides a simplified approach to understanding how asset characteristics like expected return and Beta can influence portfolio construction. Follow these steps to effectively use the tool:

  1. Input Asset Details:
    • Enter the names for your two assets (e.g., "Apple Stock", "Vanguard S&P 500 ETF").
    • Input the Expected Annual Return for each asset. These are your projections based on historical data, analyst forecasts, or financial models. Express them as percentages (e.g., 10 for 10%).
    • Input the Beta for each asset. This measures the asset's volatility relative to the market. A Beta of 1.0 moves with the market, >1.0 is more volatile, <1.0 is less volatile.
    • Enter the Market Expected Return. This is the benchmark return you're comparing against (often based on historical market averages).
  2. Validate Inputs: Ensure all numbers are positive where appropriate (returns can be negative, but Betas are typically positive). The calculator will provide inline error messages if values are missing or invalid.
  3. Calculate Weights: Click the "Calculate Weights" button. The calculator will process the inputs and display the suggested portfolio weights, intermediate results, and a primary highlighted suggestion.
  4. Interpret Results:
    • Primary Highlighted Result: This typically emphasizes the suggested weight for one of the assets, often based on a heuristic that balances risk and return.
    • Asset Weights: These indicate the proportion of your total investment that should be allocated to each asset. Ensure they sum to 100% (or 1.0).
    • Portfolio Expected Return: The weighted average expected return of your constructed portfolio.
    • Portfolio Beta: The weighted average Beta, indicating the overall volatility of your portfolio relative to the market.
    • Chart: The visual representation helps quickly grasp the proposed allocation.
    • Table: Review your input parameters for clarity.
  5. Refine and Decide: Use the results as a starting point. Consider your personal risk tolerance, time horizon, and diversification needs. Adjust inputs or explore different asset combinations to see how they impact the portfolio's risk and return profile. Use the "Copy Results" button to save or share your findings.
  6. Reset: If you want to start over or experiment with different scenarios, click "Reset Defaults" to return the inputs to their initial values.

Decision-Making Guidance:

  • High Portfolio Beta: If the calculated portfolio Beta is significantly above 1.0, it suggests a higher-risk portfolio that may experience larger swings in value. Consider increasing the weight of lower-Beta assets if this exceeds your risk tolerance.
  • Low Portfolio Beta: A Beta well below 1.0 indicates a more conservative portfolio, likely less volatile but potentially with lower returns during strong market rallies.
  • Expected Return vs. Risk: Evaluate if the Portfolio Expected Return justifies the Portfolio Beta. A high expected return with a very high Beta might be attractive to aggressive investors, while a moderate return with low Beta suits conservative ones.

Key Factors That Affect Portfolio Weighting Results

While Beta and Expected Return are critical inputs, several other factors significantly influence portfolio weighting decisions and the ultimate performance of your investments. Understanding these nuances is key to robust portfolio construction.

  1. Asset Correlation: This is perhaps the most crucial factor missing from this simplified calculator but vital in true optimization (MPT). Correlation measures how two assets move in relation to each other. Low or negative correlation allows for diversification benefits, reducing overall portfolio risk without necessarily sacrificing return. Combining assets that move independently can smooth out volatility.
  2. Investment Horizon: The length of time you plan to stay invested dramatically impacts asset allocation. Longer horizons (e.g., 10+ years) can accommodate higher-risk, higher-return assets (like growth stocks with high Betas) because there's more time to recover from potential downturns. Shorter horizons (e.g., nearing retirement) typically call for more conservative allocations with lower Betas and stable assets.
  3. Risk Tolerance: An investor's psychological and financial capacity to withstand market fluctuations is paramount. Aggressive investors might embrace high Beta assets for potentially higher returns, while conservative investors will prioritize lower Beta assets to minimize volatility, even if it means accepting lower expected returns. This calculator provides insights, but personal comfort with risk is the final arbiter.
  4. Inflation Rates: Inflation erodes the purchasing power of returns. Investments must aim to generate returns that outpace inflation to achieve real growth. When considering expected returns, it's often beneficial to think in 'real' terms (inflation-adjusted). High inflation environments might favor assets that historically perform better during such periods, potentially influencing Beta and expected return inputs.
  5. Fees and Expenses: Investment costs (management fees, trading commissions, expense ratios) directly reduce net returns. High fees can significantly impair performance, especially over the long term. A high-fee fund with a seemingly attractive expected return might be less appealing once costs are factored in. When selecting assets or funds, always consider their fee structures.
  6. Taxes: The tax implications of investment gains (capital gains, dividends, interest) vary by jurisdiction and account type (taxable vs. tax-advantaged). Tax efficiency should be a consideration in portfolio construction. For example, assets generating significant taxable income might be held in tax-advantaged accounts where possible. Tax policies can influence the attractiveness of different asset classes.
  7. Liquidity Needs: Investors may need access to their capital on short notice. Assets vary in liquidity – how quickly and easily they can be converted to cash without significant loss of value. Highly liquid assets (like major stocks or ETFs) are generally preferred for portfolios where cash might be needed. Illiquid assets (like certain real estate or private equity) require careful consideration of timing and potential price concessions.
  8. Market Conditions and Economic Outlook: Beta and expected returns are not static. They change based on the prevailing economic environment, industry trends, and company-specific news. For instance, during economic downturns, defensive sectors (often with lower Betas) might outperform cyclical sectors (often with higher Betas). Staying informed about macroeconomic factors is crucial for dynamic portfolio management.

Frequently Asked Questions (FAQ)

What is the difference between Beta and Alpha?
Beta measures systematic risk (market-related volatility). Alpha measures an investment's performance relative to its expected return, given its Beta. Positive alpha suggests outperformance beyond what market exposure would predict, often attributed to manager skill. This calculator focuses on Beta for risk assessment.
Can portfolio Beta be negative?
Yes, technically, although it's rare for individual stocks or broad funds. Assets with negative Beta tend to move in the opposite direction of the market. Gold or certain inverse ETFs are sometimes cited as examples. Including such assets can significantly hedge portfolio risk.
How often should I rebalance my portfolio weights?
Rebalancing frequency depends on your strategy and market volatility. Common approaches include rebalancing quarterly, annually, or when asset allocations drift beyond a predetermined threshold (e.g., +/- 5% from target weights). Regular monitoring is key. Consider using tools for [portfolio rebalancing analysis](https://www.example.com/portfolio-rebalancing).
Is a higher Expected Return always better?
Not necessarily. A higher expected return often comes with higher risk (higher Beta or volatility). The "best" expected return is one that aligns with your risk tolerance and overall financial goals. It's the risk-adjusted return that truly matters.
What if my assets have very different Betas?
If your assets have significantly different Betas, their weights will heavily influence the overall portfolio Beta. A large weight in a high-Beta asset will increase portfolio risk, while a large weight in a low-Beta asset will decrease it. This calculator helps quantify that impact. For example, see our guide on [managing portfolio risk](https://www.example.com/managing-portfolio-risk).
Does this calculator consider asset correlations?
No, this specific calculator simplifies the process by focusing on individual asset Expected Returns and Betas. True portfolio optimization, like Markowitz MPT, requires including correlation coefficients between assets to effectively model diversification benefits and minimize portfolio variance.
Can I use this for more than two assets?
This calculator is designed for two primary assets plus a market benchmark. For portfolios with more than two assets, more complex optimization software or advanced financial modeling techniques are required to determine optimal weights that consider all pairwise correlations and risk contributions. You might explore [diversification strategies](https://www.example.com/diversification-strategies) for more insights.
What is a "reasonable" Beta?
A Beta of 1.0 represents market-like volatility. Betas between 0.7 and 1.3 are common for individual stocks within broad market indices. Betas below 0.7 suggest lower volatility (e.g., defensive stocks, utilities), while Betas above 1.3 indicate higher volatility (e.g., growth stocks, tech companies). Betas can technically range from negative infinity to positive infinity, but practical values are usually within a narrower band.
How does the Market Expected Return impact the weights?
The Market Expected Return serves as a benchmark. While not directly used in the simplified weight calculation formula itself (which primarily uses asset-specific ER and Beta), it's crucial context. It helps investors gauge whether their assets' expected returns are reasonable relative to the overall market and informs risk-adjusted return expectations. High market expectations might justify higher asset Betas and vice-versa.

© 2023 Financial Tools Inc. All rights reserved. This calculator and information are for educational purposes only and do not constitute financial advice.

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portfolioChart = new Chart(chartContext, { type: 'bar', data: { labels: [], // Will be updated datasets: [{ label: 'Asset Weight (%)', data: [], // Will be updated backgroundColor: [ 'rgba(0, 74, 153, 0.6)', // Primary color 'rgba(40, 167, 69, 0.6)' // Success color ], borderColor: [ 'rgba(0, 74, 153, 1)', 'rgba(40, 167, 69, 1)' ], borderWidth: 1 }] }, options: { responsive: true, maintainAspectRatio: true, scales: { y: { beginAtZero: true, ticks: { callback: function(value) { return value + '%'; } } } }, plugins: { legend: { display: true, position: 'top', }, title: { display: true, text: 'Proposed Asset Allocation Weights' } } } }); } function updateChart(asset1Weight, asset2Weight, asset1Name, asset2Name) { if (!portfolioChart) { initializeChart(); } portfolioChart.data.labels = [asset1Name, asset2Name]; portfolioChart.data.datasets[0].data = [asset1Weight, asset2Weight]; portfolioChart.update(); } function validateInput(value, errorElement, inputElement, min, max, isEmptyAllowed = false) { var errorMsg = ""; if (!isEmptyAllowed && (value === null || value === ")) { errorMsg = "This field is required."; } else if (value !== " && (isNaN(value) || value max)) { errorMsg = "Please enter a valid number between " + min + " and " + max + "."; } if (errorElement) { errorElement.textContent = errorMsg; } if (inputElement) { if (errorMsg) { inputElement.style.borderColor = 'var(–error-color)'; } else { inputElement.style.borderColor = 'var(–border-color)'; } } return !errorMsg; } function calculatePortfolioWeights() { var isValid = true; var asset1Name = asset1NameInput.value.trim(); var asset1ER = parseFloat(asset1ExpectedReturnInput.value); var asset1Beta = parseFloat(asset1BetaInput.value); var asset2Name = asset2NameInput.value.trim(); var asset2ER = parseFloat(asset2ExpectedReturnInput.value); var asset2Beta = parseFloat(asset2BetaInput.value); var marketER = parseFloat(marketExpectedReturnInput.value); isValid &= validateInput(asset1Name, asset1NameError, asset1NameInput); isValid &= validateInput(asset1ER, asset1ExpectedReturnError, asset1ExpectedReturnInput, -50, 50); // Allowing negative returns isValid &= validateInput(asset1Beta, asset1BetaError, asset1BetaInput, 0, 5); // Beta range typically 0-5, though can be outside isValid &= validateInput(asset2Name, asset2NameError, asset2NameInput); isValid &= validateInput(asset2ER, asset2ExpectedReturnError, asset2ExpectedReturnInput, -50, 50); isValid &= validateInput(asset2Beta, asset2BetaError, asset2BetaInput, 0, 5); isValid &= validateInput(marketER, marketExpectedReturnError, marketExpectedReturnInput, 0, 30); // Market ER typically 0-30% if (!isValid) { // Clear results if any input is invalid asset1WeightDisplay.textContent = "N/A"; asset2WeightDisplay.textContent = "N/A"; portfolioExpectedReturnDisplay.textContent = "N/A"; portfolioBetaDisplay.textContent = "N/A"; primaryResultValueDisplay.textContent = "N/A"; updateChart([], [], asset1Name || "Asset 1", asset2Name || "Asset 2"); return; } // Simplified heuristic for weight calculation // This is a conceptual approach, not a rigorous optimization like Markowitz // We can aim for a simplified risk parity or a balance. // A common heuristic might be to weight assets based on their expected return relative to their risk (Beta). // Or, a simpler approach for demonstration: equalize weight if risk/return profiles are similar, // or lean towards higher ER/Beta if risk tolerance is assumed higher. // Let's use a simple approach: Equal weights if no other info, or lean based on ER/Beta ratio. // For demonstration, we will aim for a more balanced weight distribution if ERs are close, // or lean towards higher ER if Beta isn't excessively high. // A very basic split could be based on the ratio of ER to Beta, normalized. var weight1, weight2; // Calculate a score reflecting attractiveness (e.g., ER / Beta) var score1 = (asset1ER > 0 && asset1Beta > 0) ? asset1ER / asset1Beta : (asset1ER 0 && asset2Beta > 0) ? asset2ER / asset2Beta : (asset2ER 0) { weight1 = score1 / totalScore; weight2 = score2 / totalScore; } else { // If total score is zero or negative, default to equal weights weight1 = 0.5; weight2 = 0.5; } } // Ensure weights sum to 1 and are within reasonable bounds (0 to 1) weight1 = Math.max(0, Math.min(1, weight1)); weight2 = 1 – weight1; var portfolioER = (weight1 * asset1ER) + (weight2 * asset2ER); var portfolioBeta = (weight1 * asset1Beta) + (weight2 * asset2Beta); // Determine primary result – often the asset with the higher calculated weight or higher ER/Beta score var primaryWeight, primaryAssetName; if (weight1 >= weight2) { primaryWeight = weight1; primaryAssetName = asset1Name || "Asset 1"; } else { primaryWeight = weight2; primaryAssetName = asset2Name || "Asset 2"; } asset1WeightDisplay.textContent = (weight1 * 100).toFixed(2) + "%"; asset2WeightDisplay.textContent = (weight2 * 100).toFixed(2) + "%"; portfolioExpectedReturnDisplay.textContent = portfolioER.toFixed(2) + "%"; portfolioBetaDisplay.textContent = portfolioBeta.toFixed(2); primaryResultValueDisplay.textContent = (primaryWeight * 100).toFixed(2) + "%"; primaryResultLabelSpan.textContent = "Optimal Weight for " + primaryAssetName + ":"; // Update table tableAsset1Name.textContent = asset1Name || "Asset 1"; tableAsset1ER.textContent = asset1ER.toFixed(1); tableAsset1Beta.textContent = asset1Beta.toFixed(2); tableAsset2Name.textContent = asset2Name || "Asset 2"; tableAsset2ER.textContent = asset2ER.toFixed(1); tableAsset2Beta.textContent = asset2Beta.toFixed(2); tableMarketER.textContent = marketER.toFixed(1); updateChart(weight1 * 100, weight2 * 100, asset1Name || "Asset 1", asset2Name || "Asset 2"); } function resetCalculator() { asset1NameInput.value = "Asset A"; asset1ExpectedReturnInput.value = "10"; asset1BetaInput.value = "1.2"; asset2NameInput.value = "Asset B"; asset2ExpectedReturnInput.value = "8"; asset2BetaInput.value = "0.8"; marketExpectedReturnInput.value = "10"; // Clear errors asset1NameError.textContent = ""; asset1ExpectedReturnError.textContent = ""; asset1BetaError.textContent = ""; asset2NameError.textContent = ""; asset2ExpectedReturnError.textContent = ""; asset2BetaError.textContent = ""; marketExpectedReturnError.textContent = ""; // Reset input borders asset1NameInput.style.borderColor = 'var(–border-color)'; asset1ExpectedReturnInput.style.borderColor = 'var(–border-color)'; asset1BetaInput.style.borderColor = 'var(–border-color)'; asset2NameInput.style.borderColor = 'var(–border-color)'; asset2ExpectedReturnInput.style.borderColor = 'var(–border-color)'; asset2BetaInput.style.borderColor = 'var(–border-color)'; marketExpectedReturnInput.style.borderColor = 'var(–border-color)'; calculatePortfolioWeights(); // Recalculate with reset values } function copyResults() { var asset1Name = asset1NameInput.value.trim() || "Asset 1"; var asset2Name = asset2NameInput.value.trim() || "Asset 2″; var asset1Weight = asset1WeightDisplay.textContent; var asset2Weight = asset2WeightDisplay.textContent; var portfolioER = portfolioExpectedReturnDisplay.textContent; var portfolioBeta = portfolioBetaDisplay.textContent; var primaryResultText = primaryResultLabelSpan.textContent + " " + primaryResultValueDisplay.textContent; var assumptions = "Key Assumptions:\n"; assumptions += "- Asset 1: '" + asset1Name + "' | ER: " + asset1ExpectedReturnInput.value + "% | Beta: " + asset1BetaInput.value + "\n"; assumptions += "- Asset 2: '" + asset2Name + "' | ER: " + asset2ExpectedReturnInput.value + "% | Beta: " + asset2BetaInput.value + "\n"; assumptions += "- Market ER: " + marketExpectedReturnInput.value + "%\n"; var resultsText = "Portfolio Weight Calculation Results:\n\n"; resultsText += primaryResultText + "\n"; resultsText += "Asset 1 Weight: " + asset1Weight + "\n"; resultsText += "Asset 2 Weight: " + asset2Weight + "\n"; resultsText += "Portfolio Expected Return: " + portfolioER + "\n"; resultsText += "Portfolio Beta: " + portfolioBeta + "\n\n"; resultsText += assumptions; // Use the browser's Clipboard API navigator.clipboard.writeText(resultsText).then(function() { // Optional: Provide feedback to the user var copyButton = document.querySelector('button.success-btn'); var originalText = copyButton.textContent; copyButton.textContent = 'Copied!'; copyButton.style.backgroundColor = 'var(–primary-color)'; // Change color briefly setTimeout(function() { copyButton.textContent = originalText; copyButton.style.backgroundColor = 'var(–success-color)'; // Reset color }, 2000); }).catch(function(err) { console.error('Failed to copy results: ', err); alert('Failed to copy results. Please copy manually.'); }); } // Initialize chart on load document.addEventListener('DOMContentLoaded', function() { initializeChart(); resetCalculator(); // Call reset to set initial values and calculate first result });

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