future cash flows, if reasonably estimable. If the reporting unit’s fair value exceeds its carrying value, no further testing is required. If, however, the reporting unit’s carrying value exceeds its fair value, we then determine the amount of the impairment charge, if any. We recognize an impairment charge if the carrying value of the reporting unit’s goodwill exceeds its implied fair value.

We perform the impairment test for our indefinite-lived intangible assets by comparing the asset’s fair value to its carrying value. Fair value is estimated based on recent market transactions where available or projected discounted future cash flows. We recognize an impairment charge if the asset’s carrying value exceeds its estimated fair value.

At October 1, 2007, we performed the annual required impairment test of our goodwill and indefinite-lived intangible assets, which resulted in no impairment charge. For both goodwill and indefinite-lived intangible assets, changes in assumptions or circumstances, including, but not limited to, (1) long-term negative trends in our market capitalization, (2) continued escalation of fuel prices, (3) interruption to our operations due to employee strike, terrorist attack, etc. and/or (4) consolidation of competitors within the industry, which are not offset by other factors such as improved yield or an increase in Control Premiums, could result in an impairment in the year in which the change occurs and in future years. For additional information about our accounting policy for goodwill and other intangible assets, see Notes 2 and 5 of the Notes to the Consolidated Financial Statements.

Long-Lived Assets . Our flight equipment and other long-lived assets have a recorded value of $11.7 billion on our Consolidated Balance Sheet at December 31, 2007. This value is based on various factors, including the assets’ estimated useful lives and their estimated salvage values. In accordance with SFAS No. 144, “Accounting for the Impairment or Disposal of Long-Lived Assets” (“SFAS 144”), we record impairment losses on long-lived assets used in operations when events and circumstances indicate the assets might be impaired and the estimated future cash flows generated by those assets are less than their carrying amounts. The impairment loss recognized is the amount by which the asset’s carrying amount exceeds its estimated fair value.

In order to evaluate potential impairment as required by SFAS 144, we group assets at the fleet type level (the lowest level for which there are identifiable cash flows) and then estimate future cash flows based on projections of passenger yield, fuel costs, labor costs and other relevant factors. We estimate aircraft fair values using published sources, appraisals and bids received from third parties, as available. For additional information about our accounting policy for the impairment of long-lived assets, see Notes 2 and 5 of the Notes to the Consolidated Financial Statements.

Income Tax Valuation Allowance and Contingencies . In accordance with SFAS No. 109, “Accounting for Income Taxes,” deferred tax assets should be reduced by a valuation allowance if it is more likely than not that