You can set the appearance for a 2D line diagram and 3D waterfall chart as a step line:
1.If the diagram is in a document or a worksheet, double-click on the diagram to open it.
2.Double-click on the curve or on the axis label of the curve for which you would like to add step lines.
3.In the dialog box that appears, click on the Connection Line tab.
4.Check the option Connection line on and select Step Line from the Type field.
5.In the Location of the vertical line field, specify where the step is to lie between neighboring points.