Property, Equipment, Leasehold Improvements and Computer Software
Property, equipment and leasehold improvements, which are included in other assets, are stated at cost, less accumulated depreciation and amortization. Depreciation is determined using the straight-line method over the estimated useful lives of the assets, as appropriate. The estimated life is generally 40 years for company occupied real estate property, from one to 25 years for leasehold improvements, and from three to seven years for all other property and equipment. The cost basis of the property, equipment and leasehold improvements was $2.0 billion and $2.5 billion at December 31, 2013 and 2012, respectively. Accumulated depreciation and amortization of property, equipment and leasehold improvements was $1.0 billion and $1.3 billion at December 31, 2013 and 2012, respectively. Related depreciation and amortization expense was $183 million, $208 million and $199 million for the years ended December 31, 2013, 2012 and 2011, respectively.
Computer software, which is included in other assets, is stated at cost, less accumulated amortization. Purchased software costs, as well as certain internal and external costs incurred to develop internal-use computer software during the application development stage, are capitalized. Such costs are amortized generally over a four-year period using the straight-line method. The cost basis of computer software was $1.7 billion and $1.5 billion at December 31, 2013 and 2012, respectively. Accumulated amortization of capitalized software was $1.1 billion and $932 million at December 31, 2013 and 2012, respectively. Related amortization expense was $216 million, $221 million and $217 million for the years ended December 31, 2013, 2012 and 2011, respectively.
