MetLife, Inc. Notes to the Consolidated Financial Statements — (Continued) The Company’s accounting for income taxes represents management’s best estimate of various events and transactions. Deferred tax assets and liabilities resulting from temporary differences between the financial reporting and tax bases of assets and liabilities are measured at the balance sheet date using enacted tax rates expected to apply to taxable income in the years the temporary differences are expected to reverse. The realization of deferred tax assets depends upon the existence of sufficient taxable income within the carryback or carryforward periods under the tax law in the applicable tax jurisdiction. Valuation allowances are established when management determines, based on available information, that it is more likely than not that deferred income tax assets will not be realized. Factors in management’s determination include the performance of the business and its ability to generate capital gains. Significant judgment is required in determining whether valuation allowances should be established, as well as the amount of such allowances. When making such determination, consideration is given to, among other things, the following: The Company may be required to change its provision for income taxes in certain circumstances. Examples of such circumstances include when estimates used in determining valuation allowances on deferred tax assets significantly change or when receipt of new information indicates the need for adjustment in valuation allowances. Additionally, future events, such as changes in tax laws, tax regulations, or interpretations of such laws or regulations, could have an impact on the provision for income tax and the effective tax rate. Any such changes could significantly affect the amounts reported in the consolidated financial statements in the year these changes occur. The Company determines whether it is more likely than not that a tax position will be sustained upon examination by the appropriate taxing authorities before any part of the benefit can be recorded in the financial statements. A tax position is measured at the largest amount of benefit that is greater than 50% likely of being realized upon settlement. Unrecognized tax benefits due to tax uncertainties that do not meet the threshold are included within other liabilities and are charged to earnings in the period that such determination is made. The Company classifies interest recognized as interest expense and penalties recognized as a component of income tax. The Company is a party to a number of legal actions and is involved in a number of regulatory investigations. Given the inherent unpredictability of these matters, it is difficult to estimate the impact on the Company’s financial position. Liabilities are established when it is probable that a loss has been incurred and the amount of the loss can be reasonably estimated. Except as otherwise disclosed in Note 21, legal costs are recognized in other expenses as incurred. On a quarterly and annual basis, the Company reviews relevant information with respect to liabilities for litigation, regulatory investigations and litigation-related contingencies to be reflected in the Company’s consolidated financial statements. The Company considers all highly liquid securities and other investments purchased with an original or remaining maturity of three months or less at the date of purchase to be cash equivalents. Cash equivalents are stated at amortized cost, which approximates estimated fair value. 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 $1.5 billion and $2.2 billion at December 31, 2012 and 2011, respectively. Accumulated amortization of capitalized software was $932 million and $1.5 billion at December 31, 2012 and 2011, respectively. Related amortization expense was $221 million, $217 million and $189 million for the years ended December 31, 2012, 2011 and 2010, respectively. MetLife, Inc. 93 Cash and Cash Equivalents Stock-Based Compensation Other Accounting Policies Litigation Contingencies ‰ future taxable income exclusive of reversing temporary differences and carryforwards; ‰ future reversals of existing taxable temporary differences; ‰ taxable income in prior carryback years; and ‰ tax planning strategies. 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 five to 10 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 $2.5 billion at both December 31, 2012 and 2011. Accumulated depreciation and amortization of property, equipment and leasehold improvements was $1.3 billion and $1.2 billion at December 31, 2012 and 2011, respectively. Related depreciation and amortization expense was $208 million, $199 million and $151 million for the years ended December 31, 2012, 2011 and 2010, respectively. The Company grants certain employees and directors stock-based compensation awards under various plans that are subject to specific vesting conditions. The cost of all stock-based transactions is measured at fair value at grant date and recognized over the period during which a grantee is required to provide services in exchange for the award. Although the terms of the Company’s stock-based plans do not accelerate vesting upon retirement, or the attainment of retirement eligibility, the requisite service period subsequent to attaining such eligibility is considered nonsubstantive. Accordingly, the Company recognizes compensation expense related to stock-based awards over the shorter of the requisite service period or the period to attainment of retirement eligibility. An estimation of future forfeitures of stock-based awards is incorporated into the determination of compensation expense when recognizing expense over the requisite service period.