Sometimes a series of columns, bars, or lines doesn’t properly express your data. To create the most informative chart possible, you might want to combine different chart types within a single chart. You can even add one or more axes so that your data can be presented with different scales.
Click to select the data series you want to change (or, on the Chart Tools Format tab, select the data series in the Chart Elements list box).
On the Chart Tools Design tab, click the Change Chart Type button to display the Change Chart Type dialog box.
Select the chart type that you want to use for the selected series.
On the Chart Tools Format tab, select the data series in the Chart Elements list box.
Click the Format Selection button to display the Format Data Series dialog box.
Select this option to have the data plotted against a second axis, and then click Close.
Format the axis just as you’d format any other element in the chart.