Double Stacked Bar Chart

[Jim Harris]

I am looking to create a Bubble Chart that mimics something that one of my clients has created in Excel. I am attaching a file showing an example of what I need to recreate. I know that with Bubble Charts you can created a stacked bar chart effect but I need to have a chart that has an upper and lower section each with it's own stacked bar chart set of data.

Is this possible with the current charting or will I need to create two charts and place them together to get this effect?

Any help or reference to where I can see examples or tutorials would be great.

Thanks,