v2.4.0.6

Consolidated Balance Sheet (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | ---
Marketable securities | $ 232 | [1] | $ 602 | [1]
Allowance for accounts and notes receivable | $ 30 | [1] | $ 32 | [1]
Common stock, shares authorized | 2,500,000,000 | [1] | 2,500,000,000 | [1]
Common stock, par value | $ 0.01 | [1] | $ 0.01 | [1]
Common stock, shares issued | 1,749,550,587 | [1] | 1,740,529,279 | [1]
Grantor trusts, shares |  |  | 36,890,375 | [1]
Treasury stock, shares | 463,880,628 | [1] | 272,873,537 | [1]
[1] | Certain amounts have been restated to reflect a prior period adjustment. See Note 21-Accumulated Other Comprehensive Income, in the Notes to Consolidated Financial Statements.

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