spacing property allows you to control the space occupied by scaleBreaks. Value can either be in pixels (number – ex: 5) or percent (string – ex: “4%”). Percent values are relative to corresponding Axis length.
Default: “2%”var  chart =  new  CanvasJS.Chart("chartContainer",
{
 .
 .
axisY: {
     scaleBreaks: {
	     spacing: 4,
	     .
	     .
      },
.
.
},
 .
 . 
});
chart.render();