Use of estimates and judgments:
The preparation of financial statements in conformity with IFRS requires management to make judgments, estimates and assumptions that affect the application of accounting policies and the reported amounts of assets and liabilities, revenue and expenses, and the related disclosures of contingent assets and liabilities. We base our estimates and assumptions on current facts, historical experience and various other factors that we believe are reasonable under the circumstances. Our assessment of these factors forms the basis for our judgments on the carrying values of our assets and liabilities, and the accrual of our costs and expenses. Actual results could differ materially from these estimates and assumptions. We review our estimates and underlying assumptions on an ongoing basis and make revisions as determined necessary by management. Revisions are recognized in the period in which the estimates are revised and may impact future periods as well.
Key sources of estimation uncertainty and judgment: We have applied significant estimates and assumptions in the following areas which we believe could have a significant impact on our reported results and financial position: our valuations of inventory, assets held for sale and income taxes; the amount of our restructuring charges or recoveries; the measurement of the recoverable amounts of our cash generating units (CGUs, as defined below), which includes estimating future growth, profitability, discount and terminal growth rates, and the fair value of our real property; our valuations of financial assets and liabilities, pension and non-pension post-employment benefit costs, employee stock-based compensation expense, provisions and contingencies; and the allocation of the purchase price and other valuations related to our business acquisitions.
We define a CGU as the smallest identifiable group of assets that cannot be tested individually and that generates cash inflows that are largely independent of the cash inflows from other assets or groups of assets. CGUs can be comprised of a single site, a group of sites, or a line of business.
We have also applied significant judgment in the following areas: the determination of our CGUs and whether events or changes in circumstances during the relevant period are indicators that a review for impairment should be conducted, and the timing of the recognition of charges or recoveries associated with our restructuring actions. The near-term economic environment could also impact certain estimates necessary to prepare our consolidated financial statements, including the estimates related to the recoverable amounts used in our impairment testing of our non-financial assets, and the discount rates applied to our net pension and non-pension post-employment benefit assets or liabilities.
We describe our use of judgment and estimation uncertainties in greater detail in the following accounting policies.