and eventual disposition of the assets over the remaining economic life of the primary asset in the asset group. If the recoverability test indicates that the carrying value of the asset group is not recoverable, we will estimate the fair value of the asset group using appropriate valuation methodologies which would typically include an estimate of discounted cash flows. Any impairment would be measured as the difference between the asset groups carrying amount and its estimated fair value.

Goodwill and Indefinite−Lived Intangible Assets

We perform annual impairment tests on goodwill and intangible assets with indefinite lives in the fourth quarter of each fiscal year, or when events occur or circumstances change that would, more likely than not, reduce the fair value of a reporting unit or an intangible asset with an indefinite life below its carrying value. Events or changes in circumstances that may trigger interim impairment reviews include significant changes in business climate, operating results, planned investments in the reporting unit, or an expectation that the carrying amount may not be recoverable, among other factors. The impairment test requires us to estimate the fair value of our reporting units. If the carrying value of a reporting unit exceeds its fair value, the goodwill of that reporting unit is potentially impaired and we proceed to step two of the impairment analysis. In step two of the analysis, we measure and record an impairment loss equal to the excess of the carrying value of the reporting unit’s goodwill over its implied fair value should such a circumstance arise.

We generally base our measurement of the fair value of a reporting unit on a blended analysis of the present value of future discounted cash flows and the market valuation approach. The discounted cash flows model indicates the fair value of the reporting unit based on the present value of the cash flows we expect the reporting unit to generate in the future. Our significant estimates in the discounted cash flows model include: our weighted average cost of capital; long−term rate of growth and profitability of the reporting unit’s business; and working capital effects. The market valuation approach indicates the fair value of the business based on a comparison of the reporting unit to comparable publicly traded firms in similar lines of business. Significant estimates in the market valuation approach model include identifying similar companies with comparable business factors such as size, growth, profitability, risk and return on investment and assessing comparable revenue and operating income multiples in estimating the fair value of the reporting unit.

We believe the weighted use of discounted cash flows and the market valuation approach is the best method for determining the fair value of our reporting units because these are the most common valuation methodologies used within our industry, and the blended use of both models compensates for the inherent risks associated with either model if used on a stand−alone basis.

Indefinite−lived intangible assets primarily consist of acquired trade names and trademarks. In measuring the fair value for