softMax property
A soft maximum for the axis. If the series data maximum is less than this, the axis will stay at this maximum, but if the series data maximum is higher, the axis will flex to show all data.
Note: The series.softThreshold option takes precedence over this option.
API Docs: https://api.highcharts.com/highcharts/chart.parallelAxes.softMax
Implementation
double? softMax;