Bollinger Bands contain price 95% of the time.
What this means is that price moves from the upper to the lower band or vice versa.
This indicator works with volatility meaning when there is none then the bands are very closely together.
If on the other hand a candle closes over or below the band then there might be a strong indication that a trend might be starting to form.
We always watch both bands. If the upper and lower bands move appart or in opposite direction this indicates the continuation of the move.
When the bands move sideways the the move stalls. When the bands approach or come together the we expect a counter move.
Hope this helps.
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