A running total of that same money flow.
The level means nothing; its direction does. The classic use is divergence: price makes a new high, this line does not.
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: Accumulation / distribution is rising.
Divergence is easy to see afterwards and hard to trade in advance.
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