To add a chart at the bottom of existing one

1. Make a Chart Window window the active window.

2. Click the right mouse button anywhere in the chart window background on the chart for which you want to add additional chart. Chart context menu will appear.

   
3. Select the Add Chart from the context menu to add additional chart. Select the Add Symbol Chart to add additional symbol chart.
4. Resize newly created chart and begin using it.

After that Additional Chart at the bottom ofe existing chart will appear. See Formatting Chart Window to adjust it.