Standard deviation (StDev)
How widely prices spread around their average, in price units.
Formula
σ = √(Σ (P − mean)² ÷ N)
How to use it
Volatility in price units, useful for sizing stops and band widths.
In Kereon
Charts · Superchart. Default 20, population deviation.
Also called: std dev, stdev, sigma, deviation.