Graphs in Microsoft Excel typically chart time on the horizontal axis. Time is the independent variable in most relationships and dependent variables appear on the vertical axis.

Using a two-sided graph solves this dilemma by displaying the two series in relation to two different vertical scales, one on each side of the graph.

In Microsoft Excel, to draw attention to a specific marker in a line chart, drop in a thin line, think of it as a marker.

Do the same steps for the other series on the chart. How do I change a bar graph from vertical to horizontal in Excel? Click on the data series that you want to plot on a different axis.