StockVolatilitySevenDays: Measure 7-Day Stock Volatility

The StockVolatilitySevenDays function (fn_00920) in MarketXLS helps you analyze the short-term price movement of a stock by calculating its volatility (standard deviation) over a rolling seven-day period. Whether you’re day trading or managing long-term investments, monitoring recent volatility can provide valuable insight into near-term risk and price fluctuations.

Why Use This Function?

• Quickly get a measure of how much a stock’s price has fluctuated in the past week.
• Identify high-volatility symbols that might be riskier or ripe for momentum-based strategies.
• Compare the short-term volatility of multiple symbols side by side.
• Integrate the volatility metric into other Excel-based analytics or trading strategies.
• Useful for short-term traders, options traders looking at near-term implied moves, or conservative investors wanting to gauge risk levels.

How to Use in Excel

=StockVolatilitySevenDays(Symbol)

• Simply enter your chosen symbol (e.g., “AAPL”), and the function returns the standard deviation of daily returns over the past seven calendar (or trading) days.
• If the symbol is invalid or if insufficient data is available, you’ll get “NA.”
• Make sure your MarketXLS license is valid; an invalid or expired license will output a licensing message.

Parameters Explained

Notes and Behaviors:

• The function checks if the symbol exists and if there are at least two valid trading days of data in the last 7 days. Fewer than 2 data points leads to “NA” or an “Insufficient data” message from the backend.
• The volatility is calculated based on daily returns (i.e., day-over-day percentage changes).

Example Usage

Basic Examples

1. Simple call for a US stock symbol:
   • In cell A1: type the symbol “AAPL”.
   • In any other cell, enter:
   =StockVolatilitySevenDays(A1)
   • The function will return the 7-day standard deviation of Apple’s daily returns.

2. Hard-coded symbol:
   =StockVolatilitySevenDays("TSLA")
   • Retrieves the last 7 days of Tesla stock data and calculates its volatility.

Advanced Scenarios

• Comparing Multiple Symbols:
Suppose you have a column of symbols (e.g., in cells A2:A10). In column B, you could apply:
=StockVolatilitySevenDays(A2)
then drag down to get each symbol’s 7-day volatility. Great for building watchlists and quickly spotting which stocks have higher short-term volatility.

• Strategy Integrations:
You can combine StockVolatilitySevenDays with other MarketXLS functions, like RSI or average trading volume. For example, you might screen for stocks with high current volatility but low RSI, indicating potentially oversold but volatile conditions.

• Edge Cases / Symbol Types:

• Indices (e.g., "^GSPC") might return “NA” if insufficient data is available.
• If a symbol has not traded for several days, the function may not compute standard deviation properly due to incomplete daily returns.

Common Questions and Troubleshooting

1. “Why am I getting ‘NA’?”

   • The symbol might be invalid, spelled incorrectly, or simply no data in the last 7 days.
   • Check your license status; an expired or invalid license triggers a message rather than the volatility result.

2. “How can I confirm the data sources for the calculation?”

   • MarketXLS automatically queries the data from historical sources. The function’s internal calls fetch daily adjusted close prices for the last 7 days and then compute the standard deviation of the returns.

3. “Do I need to separately calculate daily returns?”

   • No. The function calculates daily returns (day-over-day) under the hood and then computes standard deviation, so no extra steps are needed from the user perspective.

4. “What happens if there are fewer than two trading days in the last 7 days for the symbol?”

   • The function cannot compute a standard deviation properly, so it either returns “NA” or an error message indicating insufficient data points.

Remember:

• Always ensure you’re passing a valid ticker symbol (in quotes or referencing a cell).
• Keep your MarketXLS add-in updated for the most accurate data coverage.
• This function is particularly handy for short-term volatility analysis in the real US market, but also check coverage for symbols you’re interested in.

Using the StockVolatilitySevenDays function in Excel with MarketXLS is a straightforward way to quickly gauge a stock’s near-term price fluctuations. With just one parameter, you can incorporate immediate volatility checks into your spreadsheets and inform better trading or investment decisions.