Time Weighted Calculation

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Time-Weighted Return Calculator

Measure your investment performance objectively.

Investment Performance Calculator

Enter the starting value of your investment portfolio.
Enter the ending value of your investment portfolio.
Sum of all money added to the portfolio during the period.
Sum of all money taken out of the portfolio during the period.
How many distinct periods are there within the main period? (e.g., monthly, quarterly). Must be between 1 and 10.

Calculation Results

–.–%
Period Return 1: –.–%
Period Return 2: –.–%
Period Return 3: –.–%
Weighted Average Return: –.–%
Formula Used: Time-Weighted Return (TWR) geometrically links the returns of sub-periods. It isolates the investment manager's performance by removing the distorting effects of cash flows. The basic idea is to calculate the return for each sub-period (between cash flows) and then multiply these returns together.

Calculation:
  1. For each sub-period (between cash flows), calculate the return: (End Value – Beginning Value) / Beginning Value. Handle deposits and withdrawals by adjusting the period end value.
  2. Link the returns: (1 + Period Return 1) * (1 + Period Return 2) * … * (1 + Period Return N) – 1

Key Assumptions

Initial Value: $–
Final Value: $–
Total Contributions: $–
Total Withdrawals: $–
Sub-Periods Considered:
Results copied successfully!

Investment Performance Over Sub-Periods

Period Return
Cumulative TWR

{primary_keyword}

The Time-Weighted Return (TWR) is a crucial metric in investment performance measurement. It allows investors and portfolio managers to assess the actual performance of an investment strategy over a specific period, independent of the timing and size of cash inflows and outflows. Unlike money-weighted returns, which are influenced by when an investor adds or withdraws funds, TWR focuses solely on the investment's growth. This makes it an invaluable tool for comparing the performance of different fund managers or investment strategies on an apples-to-apples basis.

What is {primary_keyword}?

{primary_keyword}, also known as the geometric linking method, is a standardized way to calculate the performance of an investment portfolio over time. It effectively breaks down the total return into smaller, discrete sub-periods, typically divided by the dates of significant cash flows (contributions or withdrawals). The return for each sub-period is calculated separately, and then these individual returns are geometrically linked to determine the overall performance for the entire measurement period. The primary goal of {primary_keyword} is to eliminate the impact of money management decisions – such as adding or withdrawing capital – and isolate the performance generated by the investment strategy itself.

Who Should Use It:

  • Investment Managers: To demonstrate their skill and the effectiveness of their investment strategies without being penalized or overly rewarded by client cash flow timing.
  • Institutional Investors: To benchmark the performance of external fund managers.
  • Financial Advisors: To report performance to clients accurately and transparently.
  • Sophisticated Individual Investors: To gain a clearer understanding of their portfolio's true growth drivers.

Common Misconceptions:

  • TWR is the same as the actual return I received: Not necessarily. Your actual personal return is a money-weighted return, directly affected by the timing of your deposits and withdrawals. TWR shows what the portfolio *would have* earned without those timing effects.
  • TWR accounts for all risk: While TWR measures performance, it doesn't inherently account for the level of risk taken to achieve that return. Metrics like the Sharpe Ratio are needed for risk-adjusted performance.
  • TWR is always higher than Money-Weighted Return: This is not true. TWR can be higher, lower, or the same as MWR depending on whether cash flows were added during periods of strong or weak performance.

{primary_keyword} Formula and Mathematical Explanation

The core principle behind {primary_keyword} is to eliminate the effect of cash flows. This is achieved by dividing the total measurement period into smaller sub-periods, usually defined by the dates of cash flows. The return for each sub-period is calculated, and then these returns are geometrically linked.

Let's define the terms:

Variables Used in Time-Weighted Return Calculation
Variable Meaning Unit Typical Range
$V_B$ Beginning Value of a sub-period Currency (e.g., USD) ≥ 0
$V_E$ Ending Value of a sub-period (before considering cash flows within that sub-period) Currency (e.g., USD) ≥ 0
$C$ Value of Cash Flows (Contributions – Withdrawals) during the sub-period Currency (e.g., USD) Can be positive (contributions) or negative (withdrawals)
$V_{E, adj}$ Adjusted Ending Value for the sub-period, accounting for cash flows. Calculated as: $V_E + C$ (if C represents net outflows) or $V_E – C$ (if C represents net inflows). For simplicity in many calculators, we use: Ending Value of sub-period adjusted for cash flows occurring *within* that sub-period. Currency (e.g., USD) ≥ 0
$R_i$ Return for the i-th sub-period Percentage (%) or Decimal Varies widely
$TWR$ Time-Weighted Return for the total period Percentage (%) or Decimal Varies widely

Step 1: Calculate the return for each sub-period ($R_i$).

The return for sub-period 'i' is calculated using the beginning value and the ending value *after* accounting for any cash flows during that sub-period. If there are no cash flows within a sub-period, the calculation is straightforward:

$R_i = (V_{E, adjusted} – V_{B}) / V_{B}$

In our simplified calculator, we assume that contributions and withdrawals are aggregated and then used to adjust the portfolio value at the end of the overall period to determine the *true* performance contribution *apart* from these flows. A more precise TWR calculation requires breaking down the period by each cash flow. Our calculator simplifies this by using the total contributions and withdrawals to estimate the TWR based on the initial and final values, and the number of sub-periods to determine the linkage. The underlying calculation for each sub-period return, when cash flows are involved, would typically look like:

$R_i = \frac{V_{E} – V_{B} – \text{Net Cash Flow}}{V_{B} + \text{Net Cash Flow}}$ (where Net Cash Flow represents additions, and the denominator reflects the value at the start of the period plus any additions that occurred).

Our calculator uses a simplified model to illustrate the concept, focusing on the geometric linking of overall period returns when internal cash flows are minimal or when only the overall period's growth is considered. For accurate TWR with frequent cash flows, specialized software is needed. However, our calculator provides a strong conceptual understanding. The simplified approach for the calculator's core output assumes we can approximate the sub-period returns or that the period itself is the only 'sub-period' if no internal cash flows are specified.

For the calculator's purpose, a common simplification when cash flows are not precisely dated within the period is to calculate the overall growth and then adjust based on net flows. The geometric linking is crucial when you have multiple distinct periods.

Step 2: Geometrically Link the Sub-Period Returns.

The TWR is the product of (1 + $R_i$) for all sub-periods, minus 1.

$TWR = (1 + R_1) \times (1 + R_2) \times … \times (1 + R_n) – 1$

Where 'n' is the total number of sub-periods.

Calculator Logic Explanation: Our calculator simplifies the process. It first calculates the overall return based on initial and final values. Then, it uses the number of sub-periods to illustrate the concept of geometric linking. It calculates individual period returns as if the total growth were evenly distributed or applied to initial/final values, then links them. The primary result is often the overall growth rate adjusted for the net effect of cash flows, presented in a way that approximates TWR's intent – measuring core investment performance. Specifically, the calculator estimates period returns to demonstrate linking. If `subPeriodCount` is 1, it directly calculates the return: `(finalValue – initialValue + withdrawals – contributions) / initialValue`. If `subPeriodCount` > 1, it divides the total growth by the number of periods and links these approximated returns.

Practical Examples (Real-World Use Cases)

Example 1: Performance Over One Year

An investment portfolio starts the year with a value of $100,000. Over the year, there were no additional contributions or withdrawals. The portfolio ends the year valued at $115,000. The investor wants to know the performance.

Inputs:

  • Initial Portfolio Value: $100,000
  • Final Portfolio Value: $115,000
  • Total Contributions: $0
  • Total Withdrawals: $0
  • Number of Sub-Periods: 1 (The entire year is treated as one period)

Calculation: Since there are no cash flows and only one period, the TWR is simply the overall return. Return = ($115,000 – $100,000) / $100,000 = $15,000 / $100,000 = 0.15

Output:

  • Time-Weighted Return: 15.00%

Interpretation: The investment strategy generated a 15% return over the year, independent of any cash flow timing (as there were none).

Example 2: Quarterly Performance with Cash Flows

An investment manager is evaluated quarterly. Q1: Starts with $50,000, ends with $55,000. A $2,000 contribution is made mid-quarter. Q2: Starts with $57,000 ($55,000 from Q1 + $2,000 contribution), ends with $60,000. A $1,000 withdrawal occurs end-quarter. Q3: Starts with $59,000 ($60,000 – $1,000 withdrawal), ends with $63,000. No cash flows. Q4: Starts with $63,000, ends with $70,000. No cash flows.

Inputs (for calculator illustration – actual TWR requires more detail):

  • Initial Portfolio Value (Start of Year): $50,000
  • Final Portfolio Value (End of Year): $70,000
  • Total Contributions: $2,000
  • Total Withdrawals: $1,000
  • Number of Sub-Periods: 4 (Quarters)

Calculator Output (Simplified Approximation): Our calculator would estimate based on the overall figures. Let's see what it produces.

Actual TWR Calculation (Conceptual): * Q1 Return: To calculate precisely, we'd need the value just before the $2k contribution. Assuming it was $53k, and value rose to $55k before the contribution. The portion from $53k to $55k grew. A simpler approach is to use beginning value of $50k and ending value adjusted for cash flow. If we approximate the end-of-quarter value *before* accounting for the $2k deposit was $53k. Then the return is ($55,000 – $50,000) / $50,000 = 10% (This is a simplified view; precise TWR requires exact timing and value adjustments). * A more accurate approach for Q1: Value at start = $50,000. Contribution = $2,000. Value at end = $55,000. We need value *before* contribution. If value grew to $53,000 before the contribution, the return on the initial $50,000 was ($53,000 – $50,000)/$50,000 = 6%. Then the contribution grew to $55,000 from $53,000 + $2,000. The calculation becomes complex. * Let's use the calculator's simplified method for illustration. It calculates an *average* period growth. Total growth = $70,000 – $50,000 = $20,000. Net cash flow = $2,000 – $1,000 = $1,000. * The calculator might calculate: Overall Growth = ($70,000 – $50,000 + $1,000) / $50,000 = $21,000 / $50,000 = 42%. It would then link this over 4 periods. * *Actual TWR requires meticulous calculation of each sub-period's return.* Let's illustrate with hypothetical, clean sub-period returns: * Q1: 5% * Q2: 3% (after withdrawal) * Q3: 4% * Q4: 6% * Linking: (1.05) * (1.03) * (1.04) * (1.06) – 1 = 1.1887 – 1 = 0.1887 or 18.87%

Output (using hypothetical clean sub-period returns):

  • Time-Weighted Return: 18.87%

Interpretation: Despite the timing of the $2,000 contribution (potentially into a rising market) and the $1,000 withdrawal, the investment manager's strategy generated an underlying growth rate of 18.87% over the year. This allows for comparison with benchmarks or other managers.

How to Use This {primary_keyword} Calculator

Our Time-Weighted Return (TWR) calculator is designed to give you a clear understanding of your investment's performance, stripping away the influence of cash flow timing. Follow these simple steps:

  1. Gather Your Data: You'll need the starting value of your portfolio for the period, the ending value, the total sum of all contributions made during the period, and the total sum of all withdrawals. You also need to decide how many distinct sub-periods you want to consider (e.g., 1 for the whole year, 4 for quarterly, 12 for monthly).
  2. Input Values:
    • Enter the Initial Portfolio Value at the very beginning of your chosen measurement period.
    • Enter the Final Portfolio Value at the very end of the measurement period.
    • Sum up all Contributions (money added) and enter the total.
    • Sum up all Withdrawals (money removed) and enter the total.
    • Specify the Number of Sub-Periods. If you're calculating for a full year and want to see quarterly performance reflected conceptually, enter 4. For a simple annual return with no intra-year cash flows, enter 1.
  3. Calculate: Click the "Calculate TWR" button.
  4. Review Results:
    • The Primary Result shows the calculated Time-Weighted Return as a percentage.
    • Intermediate Results provide insights into the calculated returns for each conceptual sub-period and a weighted average, demonstrating the geometric linking process.
    • Key Assumptions summarize the inputs you provided.
    • The Formula Explanation clarifies how the calculation works.
  5. Visualize Performance: Examine the chart, which illustrates the conceptual growth over the sub-periods and the cumulative TWR.
  6. Reset or Copy: Use the "Reset" button to clear fields and start over, or "Copy Results" to save the key figures.

Decision-Making Guidance: Compare the TWR to relevant benchmarks (like an S&P 500 index return for the same period) or the performance of other investment managers. A TWR consistently outperforming benchmarks suggests effective investment selection and management. A low or negative TWR indicates the investment strategy is not generating adequate returns. Remember that TWR measures gross performance; consider net returns after fees for your actual take-home results.

Key Factors That Affect {primary_keyword} Results

While {primary_keyword} is designed to neutralize the impact of cash flow timing, several factors are intrinsically linked to its calculation and interpretation:

  • Investment Horizon (Time): The longer the measurement period, the more pronounced the compounding effects of returns become. TWR over several years provides a more robust view of long-term strategy effectiveness than a single quarter.
  • Volatility of Returns: High volatility in sub-period returns can significantly impact the final TWR due to the geometric linking. Periods of sharp gains followed by sharp losses will result in a lower TWR than steady, consistent gains, even if the arithmetic average return is the same. For instance, two periods averaging 10% each: steady growth (1.10 * 1.10 = 1.21, or 21% total) versus volatile growth (e.g., 1.20 * 1.00 = 1.20, or 20% total).
  • Accuracy of Valuations: TWR relies heavily on accurate portfolio valuations at the end of each sub-period. Inaccurate or infrequent valuations (especially for illiquid assets) can distort sub-period returns and, consequently, the overall TWR.
  • Frequency of Cash Flows: The more frequent the cash flows (contributions/withdrawals), the more sub-periods are created, and the more complex the TWR calculation becomes. Each cash flow event necessitates a new sub-period calculation. Our calculator simplifies this by assuming uniform growth or linking broader period returns.
  • Underlying Investment Strategy: The TWR directly reflects the success (or failure) of the chosen investment strategy – whether it's value investing, growth investing, diversification, active trading, etc. A good TWR indicates the strategy is working as intended.
  • Fees and Expenses: Our calculator typically shows gross TWR (before fees). In reality, management fees, trading costs, and administrative expenses reduce the net return realized by the investor. Always consider net returns for personal decision-making. The impact of fees is magnified by compounding over time.
  • Inflation: While TWR measures nominal return, a high TWR might still be insufficient if inflation erodes purchasing power. Real return (TWR – Inflation Rate) provides a better measure of the increase in purchasing power.
  • Taxes: Investment gains are often subject to taxes. The TWR calculation is typically pre-tax. The actual return after taxes will be lower and depends on the investor's tax jurisdiction and bracket.

Frequently Asked Questions (FAQ)

What is the difference between Time-Weighted Return (TWR) and Money-Weighted Return (MWR)?

TWR measures the compound rate of growth in a portfolio, isolating the investment manager's skill by removing the effects of cash flows. MWR (or Internal Rate of Return – IRR) measures the rate of return based on the timing and size of all cash flows into and out of the portfolio. MWR reflects the investor's actual experience, while TWR reflects the investment's performance.

Why is TWR preferred for evaluating investment managers?

TWR is preferred because it provides a consistent and unbiased measure of how well the investment strategy performed, regardless of when the client chose to invest or withdraw money. This allows for fair comparisons between managers and against benchmarks.

Does TWR account for risk?

No, TWR itself does not account for risk. It only measures the gross return. Risk-adjusted return metrics, such as the Sharpe Ratio or Sortino Ratio, are needed to evaluate performance relative to the level of risk taken.

How are contributions and withdrawals handled in TWR?

Contributions and withdrawals occurring during a measurement period necessitate breaking that period into smaller sub-periods. The return is calculated for each sub-period (from the end of one cash flow event to the next), and then these sub-period returns are geometrically linked. Our calculator simplifies this by using total cash flows and the number of sub-periods.

What does a negative TWR mean?

A negative TWR indicates that the investment strategy resulted in a loss of capital over the measured period, after accounting for the effects of cash flows. It means the portfolio's value decreased on a risk-adjusted basis.

Can TWR be used for performance comparison across different asset classes?

Yes, TWR is a universal performance metric. However, when comparing across different asset classes (e.g., stocks vs. bonds vs. real estate), you must ensure you are comparing against appropriate benchmarks for each class and consider the differing risk profiles.

Is the calculator's TWR result always exact?

Our calculator provides a strong conceptual understanding and a practical approximation of TWR, especially for periods without frequent, precisely timed cash flows. For highly accurate TWR calculations with numerous daily or intra-day cash flows, specialized financial software that precisely timestamps each transaction is required.

How important is the 'Number of Sub-Periods' input?

This input is crucial for demonstrating the geometric linking principle of TWR. A higher number of sub-periods implies more frequent cash flows or a desire to view performance in smaller segments. While our calculator uses this input to illustrate linking, true TWR requires actual sub-period returns calculated between each cash flow. Using '1' calculates the overall period return, assuming no intermediate cash flows or their effects are ignored for simplicity.

Should I use TWR or MWR for my personal investment tracking?

For tracking your personal wealth growth and understanding the impact of your saving and withdrawal decisions, MWR (often reflected in your account statement's overall return) is more relevant. For evaluating the performance of a fund manager or an investment strategy's effectiveness, TWR is the appropriate metric.

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var initialValue = parseFloat(initialValueInput.value); var finalValue = parseFloat(finalValueInput.value); var contributions = parseFloat(contributionsInput.value); var withdrawals = parseFloat(withdrawalsInput.value); var subPeriodCount = parseInt(subPeriodCountInput.value, 10); if (isNaN(initialValue) || initialValue <= 0) { initialValueError.textContent = 'Please enter a valid positive number for initial value.'; isValid = false; } if (isNaN(finalValue) || finalValue < 0) { // Final value can be 0 or positive finalValueError.textContent = 'Please enter a valid non-negative number for final value.'; isValid = false; } if (isNaN(contributions) || contributions < 0) { contributionsError.textContent = 'Please enter a valid non-negative number for contributions.'; isValid = false; } if (isNaN(withdrawals) || withdrawals < 0) { withdrawalsError.textContent = 'Please enter a valid non-negative number for withdrawals.'; isValid = false; } if (isNaN(subPeriodCount) || subPeriodCount 10) { subPeriodCountError.textContent = 'Number of sub-periods must be between 1 and 10.'; isValid = false; } return isValid; } function updateCalculator() { if (!validateInputs()) { // Clear results if validation fails primaryResultDisplay.textContent = '–.–%'; intermediateResult1Display.textContent = 'Period Return 1: –.–%'; intermediateResult2Display.textContent = 'Period Return 2: –.–%'; intermediateResult3Display.textContent = 'Period Return 3: –.–%'; intermediateResult4Display.textContent = 'Weighted Average Return: –.–%'; assumption1Display.textContent = 'Initial Value: $–'; assumption2Display.textContent = 'Final Value: $–'; assumption3Display.textContent = 'Total Contributions: $–'; assumption4Display.textContent = 'Total Withdrawals: $–'; assumption5Display.textContent = 'Sub-Periods Considered: –'; updateChart([], []); // Clear chart return; } calculateTWR(); } function calculateTWR() { if (!validateInputs()) { return; } var initialValue = parseFloat(initialValueInput.value); var finalValue = parseFloat(finalValueInput.value); var contributions = parseFloat(contributionsInput.value); var withdrawals = parseFloat(withdrawalsInput.value); var subPeriodCount = parseInt(subPeriodCountInput.value, 10); var periodReturns = []; var cumulativeTWR = []; var periodReturnValues = []; // For chart // Simplified TWR calculation logic // This logic aims to approximate TWR by linking conceptual period returns. // True TWR requires precise dates of cash flows to subdivide periods. var totalGrowth = finalValue – initialValue; var netCashFlow = contributions – withdrawals; // Positive means more in than out // Calculate adjusted final value if considering cash flow's effect on growth // A common simplification: Growth Rate = (Ending Value – Beginning Value + Net Cash Flow Out) / (Beginning Value + Net Cash Flow In) // Or more simply for TWR approximation: (End Value – Begin Value) / (Begin Value adjusted for flows) // For our calculator, we'll calculate overall growth and link it across sub-periods. var overallPeriodReturn = (finalValue – initialValue) / initialValue; // Basic overall return if (subPeriodCount === 1) { // Single period calculation var adjustedFinalValue = finalValue; // Assuming no intra-period flows for simplicity var netChange = adjustedFinalValue – initialValue; var returnRate = netChange / initialValue; periodReturnValues.push(returnRate); // One value for chart primaryResultDisplay.textContent = formatPercentage(returnRate); intermediateResult1Display.textContent = 'Period 1 Return: ' + formatPercentage(returnRate); intermediateResult2Display.textContent = "; intermediateResult3Display.textContent = "; intermediateResult4Display.textContent = 'Weighted Avg Return: ' + formatPercentage(returnRate); // Same as P1 for 1 period cumulativeTWR.push(returnRate); } else { // Multiple sub-periods – approximate returns and link them // This is a simplification. In reality, each sub-period's start/end values and cash flows are needed. // We'll approximate by dividing the overall growth and linking. // Let's calculate the total growth factor var totalGrowthFactor = (finalValue + withdrawals – contributions) / initialValue; // Adjusted for flows to reflect underlying growth // If we assume growth happened smoothly, we can link it. // Let's calculate an approximate period growth factor by taking the Nth root. var approximatePeriodGrowthFactor = Math.pow(totalGrowthFactor, 1 / subPeriodCount); // Calculate individual period returns and link them var currentLinkedReturn = 1.0; for (var i = 0; i < subPeriodCount; i++) { var periodReturn = approximatePeriodGrowthFactor – 1; periodReturnValues.push(periodReturn); // Store for chart currentLinkedReturn *= (1 + periodReturn); if (i < 3) { // Display up to 3 intermediate results intermediateResult1Display.textContent = 'Period ' + (i + 1) + ' Return: ' + formatPercentage(periodReturn); if (i === 0) intermediateResult2Display.textContent = ''; if (i === 1) intermediateResult3Display.textContent = ''; } } // Fill remaining intermediate results if needed if (subPeriodCount < 3) { for (var i = subPeriodCount; i < 3; i++) { if (i === 0) intermediateResult1Display.textContent = 'Period ' + (i + 1) + ' Return: –.–%'; if (i === 1) intermediateResult2Display.textContent = 'Period ' + (i + 1) + ' Return: –.–%'; if (i === 2) intermediateResult3Display.textContent = 'Period ' + (i + 1) + ' Return: –.–%'; } } var finalTWR = currentLinkedReturn – 1; primaryResultDisplay.textContent = formatPercentage(finalTWR); intermediateResult4Display.textContent = 'Compound TWR: ' + formatPercentage(finalTWR); // Cumulative returns for chart series var currentCumulative = 1.0; for(var i = 0; i 0) { for (var i = 0; i < periodReturns.length; i++) { labels.push('Period ' + (i + 1)); periodReturnData.push(periodReturns[i]); cumulativeReturnData.push(cumulativeReturns[i]); } } else { labels.push('Overall'); periodReturnData.push(0); cumulativeReturnData.push(0); } if (chart) { chart.destroy(); // Destroy previous chart instance if it exists } chart = new Chart(ctx, { type: 'bar', // Use bar for period returns, line for cumulative data: { labels: labels, datasets: [{ label: 'Period Return', data: periodReturnData, backgroundColor: 'rgba(0, 74, 153, 0.6)', // Primary color, semi-transparent borderColor: 'rgba(0, 74, 153, 1)', borderWidth: 1, yAxisID: 'y-axis-1', type: 'bar' // Explicitly set type }, { label: 'Cumulative TWR', data: cumulativeReturnData, borderColor: 'rgba(40, 167, 69, 1)', // Success color backgroundColor: 'rgba(40, 167, 69, 0.2)', borderWidth: 2, fill: false, yAxisID: 'y-axis-2', type: 'line' // Explicitly set type }] }, options: { responsive: true, maintainAspectRatio: true, scales: { 'y-axis-1': { type: 'linear', position: 'left', ticks: { callback: function(value) { return (value * 100).toFixed(1) + '%'; } }, grid: { drawOnChartArea: true, } }, 'y-axis-2': { type: 'linear', position: 'right', ticks: { callback: function(value) { return (value * 100).toFixed(1) + '%'; } }, grid: { drawOnChartArea: false, // Only draw grid lines for the primary axis } }, x: { grid: { display: false } } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || ''; if (label) { label += ': '; } if (context.parsed.y !== null) { label += (context.parsed.y * 100).toFixed(2) + '%'; } return label; } } }, legend: { display: false // We use custom legend } } } }); } function resetCalculator() { initialValueInput.value = '10000'; finalValueInput.value = '12000'; contributionsInput.value = '500'; withdrawalsInput.value = '200'; subPeriodCountInput.value = '3'; clearErrors(); calculateTWR(); // Recalculate with default values } function copyResults() { var initialValue = parseFloat(initialValueInput.value); var finalValue = parseFloat(finalValueInput.value); var contributions = parseFloat(contributionsInput.value); var withdrawals = parseFloat(withdrawalsInput.value); var subPeriodCount = parseInt(subPeriodCountInput.value, 10); var primaryResult = primaryResultDisplay.textContent; var intermediate1 = intermediateResult1Display.textContent; var intermediate2 = intermediateResult2Display.textContent; var intermediate3 = intermediateResult3Display.textContent; var weightedAvg = intermediateResult4Display.textContent; var assumption1 = assumption1Display.textContent; var assumption2 = assumption2Display.textContent; var assumption3 = assumption3Display.textContent; var assumption4 = assumption4Display.textContent; var assumption5 = assumption5Display.textContent; var textToCopy = "— Time-Weighted Return Calculation —\n\n"; textToCopy += "Primary Result: " + primaryResult + "\n\n"; textToCopy += "Intermediate Results:\n"; textToCopy += "- " + intermediate1 + "\n"; if (intermediate2.includes(':') && !intermediate2.includes('–.–%')) textToCopy += "- " + intermediate2 + "\n"; if (intermediate3.includes(':') && !intermediate3.includes('–.–%')) textToCopy += "- " + intermediate3 + "\n"; textToCopy += "- " + weightedAvg + "\n\n"; textToCopy += "Key Assumptions:\n"; textToCopy += "- " + assumption1 + "\n"; textToCopy += "- " + assumption2 + "\n"; textToCopy += "- " + assumption3 + "\n"; textToCopy += "- " + assumption4 + "\n"; textToCopy += "- " + assumption5 + "\n"; navigator.clipboard.writeText(textToCopy).then(function() { var copyMessage = document.getElementById('copiedMessage'); copyMessage.style.display = 'block'; setTimeout(function() { copyMessage.style.display = 'none'; }, 3000); }).catch(function(err) { console.error('Could not copy text: ', err); alert('Failed to copy results. Please copy manually.'); }); } function toggleFaq(element) { var answer = element.nextElementSibling; var allAnswers = element.parentElement.parentElement.querySelectorAll('.faq-answer'); allAnswers.forEach(function(ans) { if (ans !== answer) { ans.style.display = 'none'; ans.previousElementSibling.querySelector('.faq-question').style.fontWeight = 'bold'; } }); if (answer.style.display === 'block') { answer.style.display = 'none'; element.style.fontWeight = 'bold'; } else { answer.style.display = 'block'; element.style.fontWeight = 'normal'; } } // Initial calculation on page load document.addEventListener('DOMContentLoaded', function() { // Ensure Chart.js is available. If not, this will throw an error. // For a self-contained file, Chart.js would need to be included or replaced. // Assuming Chart.js is globally available for this snippet. if (typeof Chart !== 'undefined') { updateChart([], []); // Initialize empty chart calculateTWR(); } else { console.error("Chart.js is not loaded. Please include Chart.js library."); // Optionally, provide a message to the user or skip chart functionality } });

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