The Postal Service's space-reduction campaign — which also will involve relocating its Paschall station at 2904 S. 70th St. in Southwest Philadelphia and its Schuylkill branch at 2900 Grays Ferry Ave. in South Philadelphia — comes as the agency faces increasingly dire financial straits. It has posted an annual loss each year since 2007, shortly after a new requirement began forcing it to set aside $5.5 billion annually for 10 years to cover future medical costs for retirees.