STM Inc. is considering a 4-year project with an initial cost of $637,893. The project will not directly produce sales but will reduce operating costs by $257,389 a year. The equipment is depreciated straight-line to a zero book value over the life of the project. At the end of the project, the equipment will be sold for an estimated $56,205. The tax rate is 31%. The project will require $28,253 in extra inventory for spare parts and accessories. STM requires a 9% rate of return. What is the NPV of the project?