Bollinger %b indicates the position of Closing Price relative to Bollinger Bands plotted at 2 standard deviations around a 20-Day simple moving average. Bollinger also describes a separate Band Width Indicator that reflects the width of the Bollinger bands. Bollinger %b Trading Signals Bollinger describes the following signals which can be used in a trending or ranging market: Goldman Sachs is displayed with 20-day Bollinger %b.