Project management - Workplan and Fiancial plan

Hi,

   I created a shared structure for workplan and financial plan and created expenditure transactions for one of the task. I thought as the structure is shared one, the actual cost at task level of workplan will be same to the sum of the expenditure burden costs of expenditure transactions present under costing tab of financial plan tab for this task. But I see a huge dicrepency between these two values. Can anybody help wether my understanding is right or wrong in this regard? Expaling the reason for the difference?

Thanks and Regards,

Hatakesh.