Financial Review). Accordingly, the potential for impairment for these intangible assets may exist if actual revenues are significantly less than those initially forecasted or actual expenses are significantly more than those initially forecasted. Further, an asset’s expected useful life can increase estimation risk and, thus, impairment risk, as longer-lived intangibles necessarily require longer-term forecasts—it should be noted that for some assets these time spans can range up to 20 years or longer. Some of the more significant estimates and assumptions inherent in the intangible asset impairment

estimation process include: the amount and timing of projected future cash flows; the discount rate selected to measure the risks inherent in the future cash flows; and the assessment of the asset’s life cycle and the competitive trends impacting the asset, including consideration of any technical, legal, regulatory or economic barriers to entry, as well as expected changes in standards of practice for indications addressed by the asset.

The implied fair value of goodwill is determined by first estimating the fair value of the associated business segment. To estimate the fair value of each business segment, we generally use the “market approach,” where we compare the segment to similar businesses or “guideline” companies whose securities are actively traded in public markets or which have recently been sold in a private transaction. We may also use the “income approach,” where we use a discounted cash flow model in which cash flows anticipated over several periods, plus a terminal value at the end of that time horizon, are discounted to their present value using an appropriate rate of return. Some of the more significant estimates and assumptions inherent in the goodwill impairment estimation process using the “market approach” include: the selection of appropriate guideline companies; the determination of market value multiples for the guideline companies and the subsequent selection of an appropriate market value multiple for the business segment based on a comparison of the business segment to the guideline companies; and the determination of applicable premiums and discounts based on any differences in ownership percentages, ownership rights, business ownership forms, or marketability between the segment and the guideline companies; and/or knowledge of the terms and conditions of comparable transactions. When considering the “income approach,” we include the required rate of return used in the discounted cash flow method, which reflects capital market conditions and the specific risks associated with the business segment. Other estimates inherent in the “income approach” include long-term growth rates and cash flow forecasts for the business segment.

A single estimate of fair value results from a complex series of judgments about future events and uncertainties and relies heavily on estimates and assumptions (see “Estimates and Assumptions,” above). The judgments made in determining an estimate of fair value can materially impact our results of operations.

Pension and Postretirement Benefit Plans and Defined Contribution Plans

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