Select Enable for Horizontal Axis from the Zoom and Scroll area, and then select Left from the Legend list. When zooming and scrolling is enabled for a graph, then the graph includes a Zoom icon. The Zoom icon allows you to zoom in and out of a graph's plot area via its axes. Once you zoom in on an axis, you can scroll the axis. When you zoom an axis, a zoom and scroll slider appears. The dialog box should look like this: