How to Calculate Dollar Weighted Average Return

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How to Calculate Dollar Weighted Average Return (DWR)

Understand and calculate your investment performance considering cash flows.

Dollar Weighted Return Calculator

The value of your investment at the beginning of the period.
The value of your investment at the end of the period.
Sum of all money added to the investment during the period.
Sum of all money taken out of the investment during the period.
The duration of the investment period in years.

Your Investment Performance

Total Gain/Loss:
Adjusted Ending Value:
Average Investment:
Formula Used (Simplified):
DWR is essentially the internal rate of return (IRR) for a series of cash flows. It finds the discount rate at which the present value of cash inflows equals the present value of cash outflows. The simplified calculation often used to approximate DWR for a single period is:

(Ending Value – Initial Value – Net Contributions) / (Initial Value + Net Contributions + Average Weighted Contributions/Withdrawals)

A more precise calculation involves finding the IRR that solves the equation:

Ending Value = Initial Value * (1 + DWR)^T + C1*(1+DWR)^(T-t1) + C2*(1+DWR)^(T-t2) … – W1*(1+DWR)^(T-t1) – W2*(1+DWR)^(T-t2) …

Where: Ending Value = Value at the end of the period Initial Value = Value at the beginning of the period C = Contributions at time t W = Withdrawals at time t T = Total time period t = Time of cash flow relative to the start DWR = Dollar Weighted Return

For single-period calculations with lump sums at the end: (Ending Value – Initial Value – Total Contributions + Total Withdrawals) / (Initial Value + Total Contributions) ≈ DWR Our calculator uses an approximation based on total gain, initial investment, and net contributions.

Investment Growth Over Time (Simulated)

Simulated growth based on calculated DWR and adjusted values.

What is Dollar Weighted Average Return (DWR)?

The Dollar Weighted Average Return, commonly known as the Dollar Weighted Return (DWR), is a performance measure used in finance to evaluate the success of an investment portfolio. Unlike time-weighted returns, which measure the compound growth rate of a hypothetical single dollar invested over time, the DWR takes into account the *timing* and *size* of all cash flows (contributions and withdrawals) made into and out of the portfolio. It essentially calculates the internal rate of return (IRR) for the investment, reflecting how much money an investor actually earned based on their specific investment decisions and the actual flow of funds.

Who Should Use It? DWR is particularly relevant for individual investors who actively manage their portfolios by making regular contributions or withdrawals. It provides a more personalized view of performance compared to time-weighted returns, which are better suited for comparing the skill of investment managers irrespective of client cash flow activities. If you've added or removed significant amounts of money from your investments, understanding your DWR will give you a clearer picture of your actual investment success. It's a critical metric for assessing your personal wealth accumulation strategy.

Common Misconceptions About DWR A frequent misunderstanding is that DWR is synonymous with time-weighted return (TWR). While both measure investment performance, they do so from different perspectives. TWR isolates the investment's performance from the impact of cash flows, making it ideal for manager evaluation. DWR, on the other hand, incorporates cash flows, reflecting the investor's experience. Another misconception is that a high DWR automatically means superior investment selection; it can also be significantly boosted by well-timed, large contributions, especially when the market is rising. Conversely, a large withdrawal just before a market rally can artificially depress the DWR.

Dollar Weighted Average Return (DWR) Formula and Mathematical Explanation

Calculating the Dollar Weighted Return (DWR) is fundamentally about finding the internal rate of return (IRR) for a series of cash flows associated with an investment. The IRR is the discount rate at which the net present value (NPV) of all cash flows equals zero. For an investment portfolio, this means finding the rate that equates the present value of all money taken out (withdrawals) to the present value of all money put in (initial investment plus contributions).

The precise mathematical formulation for DWR involves solving for 'r' in the following equation:

$$0 = -PV + \sum_{i=1}^{n} \frac{CF_i}{(1+r)^{t_i}}$$

Where:

  • $PV$ = Initial Investment Value
  • $CF_i$ = Cash Flow at time $t_i$ (positive for contributions, negative for withdrawals)
  • $t_i$ = Time of the cash flow (in years) from the beginning of the period
  • $r$ = Dollar Weighted Return (the IRR we are solving for)
  • $n$ = Total number of cash flows

In simpler terms, the equation states that the initial investment (a negative cash flow at time 0) plus the present values of all subsequent cash flows (contributions minus withdrawals, adjusted for their timing) must sum to zero when discounted at the DWR.

Approximation for a Single Period: For practical purposes, especially when dealing with a single accounting period and most cash flows occurring near the end, a simplified approximation is often used. This approximation is what many basic calculators, including ours, implement for single-period analysis:

$$DWR \approx \frac{Ending \, Value – Initial \, Value – Total \, Contributions + Total \, Withdrawals}{Initial \, Value + Total \, Contributions}$$

This formula aims to capture the overall growth relative to the "invested dollars." The numerator represents the net gain or loss adjusted for external cash flows, and the denominator represents the capital that was "at risk" or invested throughout the period, with a simplification assuming contributions were made early in the period.

DWR Formula Variables
Variable Meaning Unit Typical Range
Initial Investment Value The value of the investment at the start of the period. Currency ($) ≥ 0
Ending Investment Value The value of the investment at the end of the period. Currency ($) ≥ 0
Total Contributions Sum of all funds added to the investment during the period. Currency ($) ≥ 0
Total Withdrawals Sum of all funds removed from the investment during the period. Currency ($) ≥ 0
Time Period (T) The duration of the investment period. Years > 0
Dollar Weighted Return (DWR) The annualized rate of return considering cash flows. Percentage (%) Varies (can be negative)
Cash Flow ($CF_i$) Individual contribution (+) or withdrawal (-) at a specific time. Currency ($) Varies
Time of Cash Flow ($t_i$) Time elapsed from the start of the period to the cash flow event. Years 0 ≤ $t_i$ ≤ T

Practical Examples (Real-World Use Cases)

The Dollar Weighted Return is most insightful when applied to scenarios involving active portfolio management. Here are two examples:

  1. Example 1: Growing a Retirement Account

    Sarah starts the year with $50,000 in her investment account. Throughout the year, she diligently contributes $500 each month, totaling $6,000 in contributions. At the end of the year, her account value has grown to $60,000. The time period is 1 year.

    Inputs:

    • Initial Investment: $50,000
    • Ending Investment: $60,000
    • Total Contributions: $6,000
    • Total Withdrawals: $0
    • Time Period: 1 year

    Calculation (using the approximation): Total Gain/Loss = $60,000 – $50,000 = $10,000 Net Gain Adjusted for Cash Flow = $10,000 – $6,000 (Contributions) + $0 (Withdrawals) = $4,000 Denominator = $50,000 (Initial) + $6,000 (Contributions) = $56,000 DWR ≈ $4,000 / $56,000 ≈ 0.0714 or 7.14%

    Interpretation: Sarah's Dollar Weighted Return is approximately 7.14%. This figure reflects her actual return on the money she had invested throughout the year, considering her consistent contributions. If the market had performed better, her DWR would have been higher, and vice versa. This is a more accurate representation of her personal investment success than just looking at the Ending Value.

    *Use our DWR Calculator to verify.*

  2. Example 2: Managing an Investment with Withdrawals

    John begins the year with an investment portfolio valued at $100,000. In March, he withdraws $10,000 for a down payment on a house. In September, he adds $5,000 from a bonus. By year-end, the portfolio is worth $105,000. The period is 1 year.

    Inputs:

    • Initial Investment: $100,000
    • Ending Investment: $105,000
    • Total Contributions: $5,000
    • Total Withdrawals: $10,000
    • Time Period: 1 year

    Calculation (using the approximation): Total Gain/Loss = $105,000 – $100,000 = $5,000 Net Gain Adjusted for Cash Flow = $5,000 – $5,000 (Contributions) + $10,000 (Withdrawals) = $10,000 Denominator = $100,000 (Initial) + $5,000 (Contributions) = $105,000 DWR ≈ $10,000 / $105,000 ≈ 0.0952 or 9.52%

    Interpretation: John's DWR is approximately 9.52%. This calculation shows that despite the withdrawal, the remaining investment and the timing of the bonus contribution resulted in a positive return on the capital he maintained. The higher DWR compared to the simple gain ($5,000/$100,000 = 5%) highlights the impact of the timing and amount of cash flows. This measure gives John a better sense of how effectively his capital grew given his decisions.

    *Learn more about investment performance metrics.*

How to Use This Dollar Weighted Return Calculator

Our Dollar Weighted Return calculator is designed to be intuitive and provide quick insights into your investment performance. Follow these simple steps:

  1. Input Initial Investment: Enter the total value of your investment portfolio at the very beginning of the period you wish to analyze (e.g., January 1st).
  2. Input Ending Investment: Enter the total value of your investment portfolio at the very end of the same period (e.g., December 31st).
  3. Input Total Contributions: Sum up all the money you added to the investment during the entire period. This includes regular savings, additional lump sums, etc.
  4. Input Total Withdrawals: Sum up all the money you took out of the investment during the entire period. This includes planned withdrawals, emergency fund diversions, etc.
  5. Input Time Period: Specify the duration of the analysis period in years. For example, a full calendar year is 1 year, six months is 0.5 years.
  6. Click "Calculate DWR": Once all fields are populated, click this button. The calculator will process your inputs.

How to Read Results:

  • Primary Result (Dollar Weighted Return %): This is the main output, displayed prominently. It represents the annualized rate of return that your specific investment decisions generated, considering the timing and size of your cash flows. A positive percentage indicates growth, while a negative one indicates a loss.
  • Intermediate Results:
    • Total Gain/Loss: The absolute dollar amount your investment grew or shrank by (Ending Value – Initial Value).
    • Adjusted Ending Value: This isn't directly calculated in the simplified version but represents the ending value if no cash flows occurred. It helps isolate market performance. Our calculator simplifies this by focusing on the net gain adjusted for cash flow.
    • Average Investment: This is an approximation of the capital base that generated the return, typically calculated as (Initial Investment + Total Contributions). It helps contextualize the DWR.
  • Chart: The chart visually simulates the portfolio's growth based on the calculated DWR and adjusted values, providing a dynamic representation.

Decision-Making Guidance: Compare your calculated DWR against your investment goals and benchmark returns (like market indices). If your DWR consistently lags benchmarks or your expectations, consider reviewing your investment strategy, contribution amounts, withdrawal timing, or asset allocation. Remember, DWR is sensitive to cash flow timing, so a low DWR doesn't always imply poor investment selection, but rather that your cash flow decisions may have detracted from overall performance. A high DWR can be influenced by large, timely contributions.

Key Factors That Affect Dollar Weighted Return Results

Several factors significantly influence the Dollar Weighted Return calculation, making it a comprehensive measure of personalized investment performance. Understanding these factors helps in interpreting the results and making informed financial decisions.

  • Timing of Contributions: Adding money to your portfolio just before a period of strong market growth will significantly boost your DWR. Conversely, contributing right before a downturn will depress it. The DWR gives more weight to cash flows that are present for a longer duration.
  • Size of Contributions and Withdrawals: Larger cash flows have a proportionally larger impact on the DWR. A substantial contribution during a bull market enhances returns, while a large withdrawal during a downturn reduces the capital base that would have otherwise benefited from a market recovery.
  • Initial Investment Amount: The starting capital sets the baseline. A larger initial investment, if managed well, can generate significant absolute returns, contributing positively to the DWR, especially if subsequent cash flows are managed efficiently.
  • Investment Horizon (Time Period): The length of the period over which the DWR is calculated is crucial. Longer periods allow for the compounding effect to become more pronounced and provide more opportunities for cash flows to impact the overall return. Annualizing the return helps compare performance across different timeframes.
  • Market Volatility and Performance: The overall performance of the underlying assets in the portfolio is fundamental. Strong market returns increase the ending value and potential gains, positively affecting DWR. High volatility, however, can magnify the impact of cash flow timing. If you withdraw during a crash or invest just before it, your DWR will be significantly impacted.
  • Fees and Expenses: Investment management fees, trading costs, and other expenses reduce the net returns. These costs directly impact the ending value of the portfolio and thus reduce the calculated DWR. Higher fees erode returns more significantly over time. Explore ways to manage investment costs.
  • Inflation: While DWR is a nominal return, its real value is diminished by inflation. A high DWR might still result in a low or negative real return if inflation is higher than the calculated rate. Investors should always consider the purchasing power of their returns.
  • Taxes: Investment gains are often subject to taxes (capital gains tax, income tax on dividends). These taxes reduce the net amount available to the investor, thereby lowering the effective DWR. Tax-efficient investing strategies can help mitigate this impact. Understanding your tax implications is key.

Frequently Asked Questions (FAQ)

What is the main difference between DWR and TWR?

The primary difference lies in how they handle cash flows. Time-Weighted Return (TWR) removes the impact of investor contributions and withdrawals, measuring the portfolio's performance as if only a single dollar was invested. Dollar-Weighted Return (DWR), conversely, incorporates the timing and size of all cash flows, reflecting the investor's actual experience and the return on their specific capital deployed. TWR is used to evaluate investment managers' skill, while DWR assesses an individual investor's success.

Can DWR be higher than TWR?

Yes, DWR can be higher than TWR if the investor makes significant contributions during periods of strong market performance or withdrawals during periods of weak market performance. Conversely, DWR can be lower than TWR if contributions are made before downturns or withdrawals are made before upturns.

Is DWR always annualized?

The DWR calculation itself gives a rate that reflects the total period. However, it's standard practice to annualize the DWR to provide a comparable measure across different investment periods. Our calculator provides an annualized result assuming the inputs cover the full period.

How accurate is the DWR approximation formula used in calculators?

The approximation formula (Ending Value – Initial Value – Net Contributions) / (Initial Value + Contributions) is generally accurate for single periods where cash flows are either lump sums at the end or evenly distributed. However, for portfolios with frequent or large intra-period cash flows at varying times, the exact IRR calculation provides a more precise DWR. Our calculator uses the common approximation for simplicity and ease of use.

What does a negative DWR mean?

A negative Dollar Weighted Return indicates that the investment lost value over the period, considering the impact of all contributions and withdrawals. This could be due to poor market performance, high fees, ill-timed cash flows, or a combination of these factors. It means the total value of the investor's capital decreased.

How often should I calculate my DWR?

It's advisable to calculate your DWR at least annually, particularly after the end of a fiscal year or a significant portfolio event (like a large contribution or withdrawal). For active traders or those making frequent adjustments, calculating it quarterly might offer more timely insights into performance relative to their actions.

Can DWR be used for comparing different investments?

DWR is best used for evaluating the performance of a *single* investment portfolio relative to the investor's specific cash flow actions. Comparing the DWR of two different portfolios directly can be misleading if the investors' cash flow patterns (timing and size) are significantly different. TWR is the preferred metric for comparing the inherent performance of different investment strategies or managers.

What if I have many small contributions and withdrawals?

If you have numerous small cash flows throughout the period, an exact IRR calculation is more appropriate than the simplified approximation. Spreadsheets or specialized financial software can handle these complex calculations. For practical purposes, summing them up as 'Total Contributions' and 'Total Withdrawals' in our calculator provides a reasonable estimate, especially if the timing differences aren't extreme. Reviewing portfolio management strategies can help streamline this.
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function calculateDWR() { // Get input values var initialInvestment = parseFloat(document.getElementById("initialInvestment").value); var endingInvestment = parseFloat(document.getElementById("endingInvestment").value); var totalContributions = parseFloat(document.getElementById("totalContributions").value); var totalWithdrawals = parseFloat(document.getElementById("totalWithdrawals").value); var timePeriod = parseFloat(document.getElementById("timePeriod").value); // Clear previous error messages document.getElementById("initialInvestmentError").innerText = ""; document.getElementById("endingInvestmentError").innerText = ""; document.getElementById("totalContributionsError").innerText = ""; document.getElementById("totalWithdrawalsError").innerText = ""; document.getElementById("timePeriodError").innerText = ""; var isValid = true; // Validate inputs if (isNaN(initialInvestment) || initialInvestment < 0) { document.getElementById("initialInvestmentError").innerText = "Please enter a valid non-negative number."; isValid = false; } if (isNaN(endingInvestment) || endingInvestment < 0) { document.getElementById("endingInvestmentError").innerText = "Please enter a valid non-negative number."; isValid = false; } if (isNaN(totalContributions) || totalContributions < 0) { document.getElementById("totalContributionsError").innerText = "Please enter a valid non-negative number."; isValid = false; } if (isNaN(totalWithdrawals) || totalWithdrawals < 0) { document.getElementById("totalWithdrawalsError").innerText = "Please enter a valid non-negative number."; isValid = false; } if (isNaN(timePeriod) || timePeriod 0) { // Approximation formula: (Ending Value – Initial Value – Net Contributions) / (Initial Value + Total Contributions) dollarWeightedReturn = (adjustedEndingValue – initialInvestment) / denominator; } else if (initialInvestment === 0 && totalContributions === 0) { // If initial investment and contributions are zero, and ending value is positive, return is infinite. If ending value is zero, it's undefined. // For simplicity, we can represent this as a very large number or indicate it's not applicable. dollarWeightedReturn = (endingInvestment === 0) ? 0 : Infinity; // Representing infinite return if initial investment is zero and ending value is positive. } var avgInvestment = initialInvestment + totalContributions; // Simplified average investment // Format results var formattedDWR = dollarWeightedReturn === Infinity ? "∞" : (dollarWeightedReturn * 100).toFixed(2) + "%"; var formattedTotalGain = totalGainOrLoss.toLocaleString(undefined, { style: 'currency', currency: 'USD' }); var formattedAdjustedEndingValue = adjustedEndingValue.toLocaleString(undefined, { style: 'currency', currency: 'USD' }); var formattedAvgInvestment = avgInvestment.toLocaleString(undefined, { style: 'currency', currency: 'USD' }); // Display results document.getElementById("dollarWeightedReturnResult").innerText = formattedDWR; document.getElementById("totalGainOrLoss").getElementsByTagName("span")[0].innerText = formattedTotalGain; document.getElementById("adjustedEndingValue").getElementsByTagName("span")[0].innerText = formattedAdjustedEndingValue; document.getElementById("averageInvestment").getElementsByTagName("span")[0].innerText = formattedAvgInvestment; // Update chart data var chartData = prepareChartData(initialInvestment, endingInvestment, totalContributions, totalWithdrawals, timePeriod, dollarWeightedReturn); updateChart(chartData.labels, chartData.series); } function resetCalculator() { document.getElementById("initialInvestment").value = "10000"; document.getElementById("endingInvestment").value = "12000"; document.getElementById("totalContributions").value = "1000"; document.getElementById("totalWithdrawals").value = "0"; document.getElementById("timePeriod").value = "1"; // Clear error messages document.getElementById("initialInvestmentError").innerText = ""; document.getElementById("endingInvestmentError").innerText = ""; document.getElementById("totalContributionsError").innerText = ""; document.getElementById("totalWithdrawalsError").innerText = ""; document.getElementById("timePeriodError").innerText = ""; calculateDWR(); // Recalculate with default values } function copyResults() { var dwrResult = document.getElementById("dollarWeightedReturnResult").innerText; var totalGain = document.getElementById("totalGainOrLoss").getElementsByTagName("span")[0].innerText; var adjEndingValue = document.getElementById("adjustedEndingValue").getElementsByTagName("span")[0].innerText; var avgInvestment = document.getElementById("averageInvestment").getElementsByTagName("span")[0].innerText; var initialInvestment = document.getElementById("initialInvestment").value; var endingInvestment = document.getElementById("endingInvestment").value; var totalContributions = document.getElementById("totalContributions").value; var totalWithdrawals = document.getElementById("totalWithdrawals").value; var timePeriod = document.getElementById("timePeriod").value; var resultsText = "— Dollar Weighted Return Results —\n\n"; resultsText += "Inputs:\n"; resultsText += "Initial Investment: $" + parseFloat(initialInvestment).toLocaleString() + "\n"; resultsText += "Ending Investment: $" + parseFloat(endingInvestment).toLocaleString() + "\n"; resultsText += "Total Contributions: $" + parseFloat(totalContributions).toLocaleString() + "\n"; resultsText += "Total Withdrawals: $" + parseFloat(totalWithdrawals).toLocaleString() + "\n"; resultsText += "Time Period: " + timePeriod + " years\n\n"; resultsText += "Outputs:\n"; resultsText += "Dollar Weighted Return: " + dwrResult + "\n"; resultsText += "Total Gain/Loss: " + totalGain + "\n"; resultsText += "Adjusted Ending Value: " + adjEndingValue + "\n"; resultsText += "Average Investment: " + avgInvestment + "\n"; // Use a temporary textarea to copy text var tempTextArea = document.createElement("textarea"); tempTextArea.value = resultsText; document.body.appendChild(tempTextArea); tempTextArea.select(); document.execCommand("copy"); document.body.removeChild(tempTextArea); // Provide feedback var copyButton = event.target; var originalText = copyButton.innerText; copyButton.innerText = "Copied!"; copyButton.style.backgroundColor = "#28a745"; setTimeout(function() { copyButton.innerText = originalText; copyButton.style.backgroundColor = "#004a99″; }, 2000); } // Charting Logic using Canvas API var myChart = null; // Variable to hold the chart instance function prepareChartData(initialInvestment, endingInvestment, totalContributions, totalWithdrawals, timePeriod, dwr) { var labels = []; var series = { 'Investment Value': [], 'Adjusted Value': [] }; var numPoints = 50; // Number of points for the chart line var step = timePeriod / (numPoints – 1); for (var i = 0; i = 0) { currentInvestmentValue = effectiveInitial * Math.pow(1 + dwr, t); } else { // For negative DWR, growth is negative. Handle potential issues with Math.pow. currentInvestmentValue = effectiveInitial * Math.pow(1 – Math.abs(dwr), t); } // Cap at 0 if calculation goes negative, though DWR ideally shouldn't result in negative portfolio value from positive start unless massive losses. currentInvestmentValue = Math.max(0, currentInvestmentValue); } series['Investment Value'].push(currentInvestmentValue); // Calculate simulated adjusted value (value without contributions/withdrawals) var adjustedValue; if (t === 0) { adjustedValue = initialInvestment; } else { if (dwr >= 0) { adjustedValue = initialInvestment * Math.pow(1 + dwr, t); } else { adjustedValue = initialInvestment * Math.pow(1 – Math.abs(dwr), t); } adjustedValue = Math.max(0, adjustedValue); } series['Adjusted Value'].push(adjustedValue); } // Ensure ending values match inputs for accuracy at the end point series['Investment Value'][numPoints – 1] = endingInvestment; series['Adjusted Value'][numPoints – 1] = initialInvestment * Math.pow(1 + dwr, timePeriod); // Recalculate adjusted ending value precisely for the end of the period. series['Adjusted Value'][numPoints – 1] = Math.max(0, series['Adjusted Value'][numPoints – 1]); return { labels: labels, series: series }; } function updateChart(labels, seriesData) { var ctx = document.getElementById('dwrChart').getContext('2d'); // Destroy previous chart instance if it exists if (myChart) { myChart.destroy(); } // Prepare datasets var datasets = []; if (seriesData['Investment Value'] && seriesData['Investment Value'].length > 0) { datasets.push({ label: 'Simulated Portfolio Value', data: seriesData['Investment Value'], borderColor: '#004a99', backgroundColor: 'rgba(0, 74, 153, 0.1)', fill: true, tension: 0.4 // Makes the line slightly curved }); } if (seriesData['Adjusted Value'] && seriesData['Adjusted Value'].length > 0) { datasets.push({ label: 'Simulated Growth (No Cash Flow)', data: seriesData['Adjusted Value'], borderColor: '#28a745', backgroundColor: 'rgba(40, 167, 69, 0.1)', fill: true, tension: 0.4 }); } if (datasets.length === 0) return; // Don't create chart if no data myChart = new Chart(ctx, { type: 'line', data: { labels: labels, datasets: datasets }, options: { responsive: true, maintainAspectRatio: false, scales: { x: { title: { display: true, text: 'Time (Years)' } }, y: { title: { display: true, text: 'Portfolio Value ($)' }, beginAtZero: true } }, plugins: { tooltip: { callbacks: { label: function(context) { var label = context.dataset.label || "; if (label) { label += ': '; } if (context.parsed.y !== null) { label += new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' }).format(context.parsed.y); } return label; } } }, legend: { position: 'top', } } } }); } // Initial calculation and chart rendering on page load document.addEventListener('DOMContentLoaded', function() { resetCalculator(); // Set default values and calculate // Trigger initial calculation to populate chart with default values calculateDWR(); }); // FAQ Toggle functionality var faqItems = document.querySelectorAll('.faq-item'); faqItems.forEach(function(item) { var question = item.querySelector('.faq-question'); question.addEventListener('click', function() { item.classList.toggle('open'); }); });

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