could you help me please. How can I show only used area on the right Y-axis.
https://jsfiddle.net/935dkrqm/1/
You currently have tickInterval: 0.2
and min: 0
set for your right Y-axis. If you remove these two settings, the Y-axis will scale to fit the data. See updated fiddle:
https://jsfiddle.net/935dkrqm/2/
I also put in a formatter for your tooltip, so that you can see the value of the percentage series properly.
tooltip: {
pointFormatter: function(){
return '<b>' + Highcharts.numberFormat(this.y * 100, 2) + '%</b>'
}
}