The time period to be used in calculating the Middle Band
The number of standard deviations away from the Middle Band that the Upper and Lower Bands should be
ReadonlydeviationThe number of standard deviations away from the Middle Band that the Upper and Lower Bands should be
Readonlyinterval
The time period to be used in calculating the Middle Band
Readonlyprices
Bollinger Bands (BBANDS) Type: Volatility
Bollinger Bands (BBANDS), developed by John A. Bollinger, are set as an envelope around a moving average. Narrow bands indicate a sideways trend (ranging markets). To determine a breakout direction, Investopia.com suggests to use the relative strength index (RSI) along with one or two volume-based indicators such as the intraday intensity index (developed by David Bostian) or the accumulation/distribution index (developed by Larry William).
When the upper and lower bands expand, there can be "M" and "W" formations. The "W" formation indicates a bullish movement and the "M" formation indicates a bearish movement.
See
https://www.investopedia.com/terms/b/bollingerbands.asp