Think I worked this one out for myself or at least a workaround for myself.
Essentially I gave up on the crosstable and loaded the budget into my SQL database.
I then created a new table from the resident new vehicle table.
Only selecting the fields that matched my budget file then I concatenated the budget file to the new table.
On each of the tow loads I simply added a field to identify whether it was actual or budget and then used set analysis for the expressions in my chart.
don't know if there was a better way of doing this but at least it works !!