PDF axis choice options — Options for specifying the axes on ... - Stata In this graph, there are two y axes and two x axes: left and right, and top and bottom. Reference Wiggins, V. L. 2010.Stata tip 93: Handling multiple y axes on twoway graphs. Stata Journal 10: 689-690. Also see [G-3] axis label options — Options for specifying axis labels [G-3] axis options — Options for specifying numeric axes