Looking for a little help reguarding using  Composite Charts

 I have the following two DataTables filed with the Following Data

        Me.dsData.Base.AddBaseRow("2 Covers", 10)
        Me.dsData.Base.AddBaseRow("4 Covers", 6)
        Me.dsData.Base.AddBaseRow("8 COvers", 4)

        Me.dsData.Booked.AddBookedRow("2 Covers", 2, 2)
        Me.dsData.Booked.AddBookedRow("4 Covers", 1, 2)
        Me.dsData.Booked.AddBookedRow("8 Covers", 2, 1)

The Base datatable stores the number tables with the corresponding covers.  When i run this as a simple stacked chart it works pefrecty as shown here 

The Booked datatable stores the number of booked and number of required tables agains the corresponding covers.  When i run this as a simple stackedcolumn chart it works perfectly as show below

My problem starts when i want to join them both on th same chart so i can show Total Number of Tables Available and also the combined total of required and booked which then shows the number remaining.  Does that make sense?

When i make up my chart in code i go to make a Numeric Series for the Stacked Chart which only allows you to add one "Value" column.  I am guessing i do not have the understanding required.  

Can anyone shed some light onto this for me

Let me know if i need to be more clear

Cheers in Advance