Previous P.O Material price in Recent PO..?

Hi gurus

Can anybody explain me how to get a previous P.O material Price in Recen P.O.

I have created One P.O, at the time release HOD want to verify the same Material price in Previous P.O ,

It is possible to see the old PO Material price in Recent PO.

if yes please Expalin me step by step.

Valuable answer is highly rewardable..

Thanks

sap-mm