the following, as appropriate: local returns policies and practices; returns as a percentage of sales; an understanding of the reasons for past returns; estimated shelf-life by product; and an estimate of the amount of time between shipment and return or lag time; and any other factors that could impact the estimate of future returns, such as loss of exclusivity, product recalls, or a changing competitive environment, as appropriate.

• We record sales incentives as a reduction of revenues at the time the related revenues are recorded or when the incentive is offered, whichever is later. We estimate the cost of our sales incentives based on our historical experience with similar incentives programs.

Historically, our adjustments to actual have not been material; on a quarterly basis, they generally have been less than 1.0% of Pharmaceutical net sales and can result in a net increase to income or a net decrease to income. The sensitivity of our estimates can vary by program, type of customer and geographic location. However, estimates associated with U.S. Medicaid and contract rebates are most at-risk for material adjustment because of the extensive time delay between the recording of the accrual and its ultimate settlement, an interval that can range up to one year. Because of this time lag, in any given quarter, our adjustments to actual can incorporate revisions of several prior quarters.

Alliances—We have agreements to co-promote pharmaceutical products discovered by other companies. Alliance revenues are earned when our co-promotion partners ship the related product and title passes to their customer. Alliance revenues are primarily based upon a percentage of our co-promotion partners’ net sales. Expenses for selling and marketing these products are included in Selling, informational and administrative expenses.

Long-Lived Assets

We review all of our long-lived assets, including goodwill and other intangible assets, for impairment indicators at least annually and we perform detailed impairment testing for goodwill and indefinite-lived assets annually and for all other long-lived assets whenever impairment indicators are present. When necessary, we record charges for impairments of long-lived assets for the amount by which the present value of future cash flows, or some other fair value measure, is less than the carrying value of these assets. Examples of those events or circumstances that may be indicative of impairment include:

• A significant adverse change in legal factors or in the business climate that could affect the value of the asset. For example, a successful challenge of our patent rights likely would result in generic competition earlier than expected.

• A significant adverse change in the extent or manner in which an asset is used. For example, restrictions imposed by the FDA or other regulatory authorities could affect our ability to manufacture or sell a product.

• A projection or forecast that demonstrates losses associated with an asset. This could include, for example, a change in a government reimbursement program that results in an inability to sustain projected product revenues and profitability. This also