Syntax
Public FunctionHistoricalVolatility(applyTo As ENUM_APPLIED_PRICE, period As Integer, BarHistory As Integer, StandardDev As Integer) As String
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Historical volatility is the log-normal standard deviation. The Historical Volatility Index is based on the book by Don Fishback, “Odds: The Key to 90% Winners”.
This formula will output a 30-day historical volatility index between 1 and 0:
Stdev(Log(Close / Close Yesterday), 30) * Sqrt(365)
Note that some traders use 252 instead of 365 for the bar history that is used in the square root calculation.
The Log value is a natural log (ie Log10).
Parameters
Key | Description |
applyTo | Value can be one of ENUM_APPLIED_PRICE |
period | Period as integer |
BarHistory | Integer value |
StandardDev | Integer value |
Return value
Returns the handles of a technical indicator, in case of failure returns an empty string.
See Also