Investopedia has an article here but it doesn’t seem terribly helpful to me. Here is a document I wrote when I was trying to come to grips with it and also what my software was showing me. Volatility I have been on something of a crusade to understand volatility and how it is calculated in my charting packages Optuma and Beyond Charts Plus. First Historical Volatility. This is the standard deviation of the % change in price for a specified period (sometimes called the Interday return). There are a few different ways this can be calculated. In Microsoft Excel, it
Volatility
