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       All majority-owned subsidiaries in which we have both share and
       management control are consolidated. All significant
       intercompany accounts and transactions are eliminated. Our
       variable interest entities in which we are the primary
       beneficiary are consolidated. Investments in unconsolidated
       affiliates and joint ventures are accounted for under the equity
       method (Note&amp;#160;13).
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       We evaluate the carrying value of our equity accounted
       investments in relation to publicly quoted market prices when
       available. If the quoted market price is below book value, and
       such decline is considered other than temporary, we write-down
       our equity investments to quoted market value.
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       We define joint ventures as businesses in which we and a small
       group of other partners each participate actively in the overall
       entity management, based on a stockholders agreement. We define
       affiliates as businesses in which we participate as a minority
       stockholder but with significant influence over the operating
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       Our participation in hydroelectric projects is made via
       consortium contracts under which we have undivided interests in
       the assets and are liable for our proportionate share of
       liabilities and expenses, which are based on our proportionate
       share of power output. We do not have joint liability for any
       obligations. No separate legal or tax status is granted to
       consortia under Brazilian law. Accordingly, we recognize our
       proportionate share of costs and our undivided interest in
       assets relating to hydroelectric projects (Note&amp;#160;12).
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