I have a need to display an area above (or below for reversed y-axis) a line. I can certainly specify a threshold above the highest value in the series, however this breaks the yAxis ability to dynamically pick the maximum end of the range based on the data. So I suggest either (a) have an option for the yAxis to ignore the threshold when dynamically choosing the min/max of the range, or (b) having special "positive infinity" and "negative infinity" values for the threshold that would of course be ignored by the yAxis ranging.

Thanks!