Depreciation, amortization and goodwill valuation: Property, plant and equipment are stated at historical cost and depreciated by the straight-line method over the estimated useful lives of the assets. Machinery and equipment are depreciated over periods ranging from 3 to 20 years, and buildings and building improvements over periods up to 50 years.
Definite life intangible assets are amortized over their estimated useful lives. Altria Group, Inc. is required to conduct an annual review of goodwill and intangible assets for potential impairment. Goodwill impairment testing requires a comparison between the carrying value and fair value of each reporting unit. If the carrying value exceeds the fair value, goodwill is considered impaired. The amount of impairment loss is measured as the difference between the carrying value and implied fair value of goodwill, which is determined using discounted cash flows. Impairment testing for non-amortizable intangible assets requires a comparison between the fair value and carrying value of the intangible asset. If the carrying value exceeds fair value, the intangible asset is considered impaired and is reduced to fair value. During 2005, Altria Group, Inc. completed its annual review of goodwill and intangible assets, and no charges resulted from this review. However, as part of the sale or pending sale of certain Canadian assets and two brands, Kraft recorded total non-cash pre-tax asset impairment charges of $269 million in 2005, which included impairment of goodwill and intangible assets of $13 million and $118 million, respectively, as well as $138 million of asset write-downs. The 2004 review of goodwill and intangible assets resulted in a $29 million non-cash pre-tax charge at Kraft related to an intangible asset impairment for a small confectionery business in the United States and certain brands in Mexico. A portion of this charge, $12 million, was recorded as asset impairment and exit costs on the consolidated statement of earnings. The remainder of the charge, $17 million, was included in discontinued operations.
Goodwill by segment was as follows:


Intangible assets were as follows:


Non-amortizable intangible assets substantially consist of brand names from Kraft’s acquisition of Nabisco Holdings Corp. (“Nabisco”) in 2000 and PMI’s 2005 acquisition in Indonesia. Amortizable intangible assets consist primarily of certain trademark licenses and non-compete agreements. Pre-tax amortization expense for intangible assets during the years ended December 31, 2005, 2004 and 2003, was $28 million, $17 million and $9 million, respectively. Amortization expense for each of the next five years is estimated to be $30 million or less, assuming no additional transactions occur that require the amortization of intangible assets.
The movement in goodwill and gross carrying amount of intangible assets is as follows:


As a result of Kraft’s common stock repurchases, ALG’s ownership percentage of Kraft has increased from 85.4% at December 31, 2004 to 87.2% at December 31, 2005, thereby resulting in an increase in goodwill. Other, above, includes this additional goodwill, as well as the 2004 reclassification to goodwill of certain amounts previously classified as indefinite life intangible assets, and 2004 tax adjustments related to the Nabisco acquisition. The increase in goodwill and intangible assets from acquisitions during 2005 is related to preliminary allocations of purchase price for PMI’s acquisitions in Indonesia and Colombia. The allocations are based upon preliminary estimates and assumptions and are subject to revision when appraisals are finalized, which will be in the first half of 2006.