You may find that after creating multiple chart report, the charts aren't loading the data as expected. This may be due to some settings required. Follow the below instructions on how to correctly configure multiple charts.
For up to two charts in a report
In the main menu, go to Create a Report.
Select the appropriate view (e.g. “CDRs View”)
On the “Data” page, drag in the appropriate columns to make the table and click the “Co-Display” check-box, so that it is selected
On the “Charts” page, add two charts by clicking the + on the bottom right
Save and Activate the report
Edit the report again, and go to the “Related Reports” page
Expand the search pane on the left, and search for your report. Drag the report over to the right, into the “Tabbed Co-Display” section
On the “Output” page, in the search pane on the left, drag the two charts into the grid that you should see in the middle and move and resize the charts as needed. Then Click on Report and then Save. Then click activate on the pop screen.
Add to a dashboard
You may need to resize the dashboard section(s) as needed to show both of the charts in their entirety. Then Click on the Save button located behind the search pop out.
For Three or More Charts in a Report
For this, reports have to be linked, and the process is more complicated.
See this link for more info: http://www.yellowfinbi.com/YFForum-Multiple-charts-in-report-not-showing-new-ones-?thread=183116 )