Property and Equipment
Depreciation is provided on a straight-line basis over the estimated useful lives of owned assets. Leasehold improvements and leased properties under capital leases are amortized over the estimated useful life of the property or over the term of the lease, whichever is shorter. Estimated useful lives range from 10 to 39 years for land improvements, buildings and building improvements; and 2 to 13 years for equipment. Major repairs, which extend the useful life of an asset, are capitalized; routine maintenance and repairs are charged against earnings. The majority of the business uses the composite method of depreciation for equipment. Therefore, gains and losses on retirement or other disposition of such assets are included in earnings only when an operating location is closed, completely remodeled or impaired. Fully depreciated property and equipment are removed from the cost and related accumulated depreciation and amortization accounts. Property and equipment consists of (in millions):
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Land and land improvements | | | | | | |
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Buildings and building improvements | | | | | | | | |
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Leased locations (leasehold improvements only) | | | | | | | | |
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Capitalized system development costs | | | | | | | | |
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Less: accumulated depreciation and amortization | | | | | | | | |
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Depreciation expense for property and equipment was $894 million in fiscal 2013, $841 million in fiscal 2012 and $809 million in fiscal 2011.
The Company capitalizes application stage development costs for significant internally developed software projects, such as upgrades to the store point-of-sale system. These costs are amortized over a five-year period. Amortization expense was $100 million in fiscal 2013, $70 million in fiscal 2012 and $58 million in fiscal 2011. Unamortized costs at August 31, 2013 and 2012, were $374 million and $292 million, respectively.