StockVolatilitySixMonths: Measure Six-Month Stock Volatility in Excel

The StockVolatilitySixMonths function helps you measure the variation (standard deviation) of a stock’s daily returns over roughly the last six months (180 calendar days). By returning a quantitative measure of volatility, you gain insights into the relative riskiness of your chosen security, all within Excel through MarketXLS.

Why Use This Function?

• Quickly assess the historical volatility of any stock or symbol for the past six months.
• Ideal for comparing which securities are more stable vs. those with wilder price swings.
• Useful in portfolio allocation, risk management, or when considering entry/exit points.
• Enables you to automate your volatility tracking right inside Excel.

How to Use in Excel

=StockVolatilitySixMonths(Symbol)

• Enter the function in any cell.
• Replace Symbol with the desired ticker (e.g., "AAPL", "GOOGL", or any supported market symbol).
• Press Enter to display the calculated six-month standard deviation of daily returns (as a decimal).

Parameters Explained

• If Symbol is invalid or if there is insufficient data over the last 180 days, the function returns "NA."
• When valid data is found, you get the standard deviation of daily returns covering roughly 180 calendar days.

Example Usage

Basic Examples

1. =StockVolatilitySixMonths("AAPL")
   • Retrieves AAPL’s standard deviation of daily returns for the last six months.
   • If the data is successfully retrieved, a numeric value is returned (e.g., 0.015 might indicate 1.5% volatility in daily returns).

2. =StockVolatilitySixMonths("GOOGL")
   • Tracks six-month volatility of Alphabet Inc.
   • Use this value to compare with AAPL or other tickers’ volatility.

3. =StockVolatilitySixMonths("INVALID")
   • Returns "NA" if an invalid symbol is passed or if the license is invalid.

Advanced Scenarios

• Combining with Other Excel Functions:
Use the result alongside Excel’s built-in statistical functions. For instance, compare =StockVolatilitySixMonths("MSFT") to an industry average or a benchmark index by referencing the same function on another symbol.

• Volatility Comparisons:
Create a table comparing =StockVolatilitySixMonths for multiple tickers (e.g., "TSLA", "AMZN", "BAC") to quickly see which stocks exhibit higher or lower volatility.

• Customized Analysis Over Time:
Though the function specifically targets a ~180-day window, you could store outputs on a rolling schedule in Excel to track how volatility changes monthly or quarterly.

Common Questions and Troubleshooting

1. “Why am I getting ‘NA’ for a valid symbol?”
   • The symbol might not have enough data for the last 180 days. New listings, for example, might have insufficient historical data.
   • License validation or data API issues can also cause an "NA" result.

2. “Is the volatility annualized?”
   • No. The function calculates the standard deviation of daily returns over approximately 180 calendar days. If you need an annualized figure, you can multiply the daily standard deviation by the square root of 252 (typical trading days in a year); however, that is not done by default in this function’s implementation.

3. “What if there are fewer than two data points?”
   • The function internally requires at least two data points to compute a standard deviation. If fewer than two points are available, you’ll see an error or "NA" output.

4. “Does it handle indices?”
   • Yes. You can pass symbols for indices (e.g., "^GSPC" for the S&P 500), provided the underlying data is available for that symbol.

By understanding and leveraging StockVolatilitySixMonths, you can seamlessly incorporate six-month volatility metrics into your Excel-based workflows, equipping you to make data-driven decisions and manage your portfolio’s risk more effectively.