plotOptions.dumbbell.threshold

The Y axis value to serve as the base for the area, for distinguishing between values above and below a threshold. The area between the graph and the threshold is filled.

• If a number is given, the Y axis will scale to the threshold.
• If null, the scaling behaves like a line series with fill between the graph and the Y axis minimum.
• If Infinity or -Infinity, the area between the graph and the corresponding Y axis extreme is filled (since v6.1.0).