This excerpt taken from the ADI 10-K filed Nov 20, 2006.
k. Use of Estimates
The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingencies at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Such estimates relate to the useful lives of fixed assets and identified intangible assets, allowances for doubtful accounts and customer returns, the net realizable value of inventory, potential reserves relating to litigation matters, accrued liabilities, accrued taxes, deferred tax valuation allowances, assumptions pertaining to share-based payments and other reserves. Actual results could differ from those estimates, and such differences may be material to the financial statements.