Reference lines are vertical or horizontal lines in a graph, corresponding with user-defined values on the x-axis and y-axis respectively.
Each graph can contain up to 16 vertical and horizontal reference lines.
Add reference line
Right-click in the graph and click Add and Horizontal reference lineor Vertical reference line.
Click in the margin of the graph to create a reference line and drag it into the graph plot area.
While you are dragging the reference line in the plot area, the corresponding value is displayed next to the reference line.
Format reference line
Right-click on the reference line and click Format reference line on the context menu.
In the dialog box you can select line color, style and width, and enter an exact value for the reference line.
Note: all reference lines in one graph have the same color style and width.
Remove reference line
Right-click on the reference line and click Remove reference line on the context menu.
Drag the reference line into the graph's margins.