Up moves minus down moves, as a share of both together.
Between −100 and +100. Unlike RSI it does not smooth, so it reacts faster and swings wider.
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.
Entry: Chande momentum(9) crosses above 50.
No smoothing means more extremes: values above 50 happen far more often than an RSI above 70.
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