How to i allocate with actual Burdened Cost Budget

Dear Sir,
I create new allocation rule with 3 projects for one task for each project. The burdened cost budget for each project and task is different. When i generate the allocation batch. The allocation amount is equal.
I think the allocation rule is not calculation base on the burdened cost budget. Because, if the calculation base on this principle , the allocation amount is different

Please, explain to me why and help me  the way to allocation with different amount,

Thanks and Best Regards,