Theory : Bollinger bands are calculated as : A Bollinger Band® is a technical analysis tool defined by a set of lines plotted two standard deviations (positively and negatively) away from a simple moving average (SMA) of the securitys price, but can be adjusted to user preferences. Bollinger Bands® were developed and copyrighted by famous technical trader John Bollinger, The part that is using standard deviations is a part that can be