JavaScript/jQuery Chart - valueAxis.constantLineStyle.label
Specifies the appearance of the labels of those constant lines that belong to the value axis.
A constant line label displays the value of a constant line.

See Also
horizontalAlignment
Aligns constant line labels in the horizontal direction.
Type:
Default Value: 'left'
position
Specifies the position of constant line labels on the chart plot.
Type:
Default Value: 'inside'
By default, constant line labels are displayed inside the chart plot near the constant lines they belong to. To place the labels outside the chart plot, set the position property to "outside".