HP states property, plant and equipment at cost less accumulated depreciation. HP capitalizes additions and improvements and expenses maintenance and repairs as incurred. Depreciation is computed using straight-line or accelerated methods over the estimated useful lives of the assets. Estimated useful lives are five to 40 years for buildings and improvements and three to 15 years for machinery and equipment. HP depreciates leasehold improvements over the life of the lease or the asset, whichever is shorter. HP depreciates equipment held for lease over the initial term of the lease to the equipment's estimated residual value. The estimated useful lives of assets used solely to support a customer services contract generally do not exceed the term of the customer contract. Upon retirement or disposition, the asset cost and related accumulated depreciation are removed with any gain or loss recognized in the Consolidated Statements of Earnings.
HP capitalizes certain internal and external costs incurred to acquire or create internal use software, principally related to software coding, designing system interfaces and installation and testing of the software. HP amortizes capitalized internal use software costs using the straight-line method over the estimated useful lives of the software, generally from three to five years.