How far price normally strays from its own average.
The raw building block under Bollinger Bands. The series '%' puts it as a percentage of price, so you can compare instruments.
Worked out by the same code the builder uses, on stored daily candles. Move a setting and the line moves with it. This is what happened, not what will happen.
Gate: Standard deviation % is below 3.
It measures size of movement, never direction.
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