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   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;10. INCOME TAXES&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The effective tax rate for the three months ended June&amp;#160;30, 2010 and 2009 was 28.2% and 24.2%,
   respectively, and the effective tax rate for the six months ended June&amp;#160;30, 2010 and 2009 was 28.8%
   and 26.4%, respectively. WESCO&amp;#8217;s three and six month effective tax rates are lower than the
   federal statutory rate of 35% primarily due to benefits resulting from the recapitalization of
   Canadian operations, which are partially offset by nondeductible expenses, state taxes and foreign
   rate differences. The effective tax rate for the six months ended June&amp;#160;30, 2010 reflects discrete
   adjustments totaling $1.2&amp;#160;million related to changes in uncertain tax positions and discrete
   adjustments totaling $0.5&amp;#160;million associated with prior years&amp;#8217; taxes. The effective tax rate for
   the six months ended June&amp;#160;30, 2009 included a discrete benefit of $0.2&amp;#160;million related to prior
   years&amp;#8217; taxes.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The total amount of unrecognized tax benefits was $8.5&amp;#160;million and $8.1&amp;#160;million as of June&amp;#160;30,
   2010 and December&amp;#160;31, 2009, respectively. If these tax benefits were recognized in the consolidated
   financial statements, the portion of these amounts that would reduce WESCO&amp;#8217;s effective tax rate
   would be $7.4&amp;#160;million and $7.1&amp;#160;million, respectively. During the next twelve months, it is
   reasonably possible that the amount of unrecognized tax benefits will decrease by $1.4&amp;#160;million due
   to the resolution of federal, state and foreign tax examinations.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;WESCO records interest related to uncertain tax positions as a part of interest expense in the
   consolidated statement of income. As of June&amp;#160;30, 2010 and December&amp;#160;31, 2009, WESCO had an accrued
   liability for interest related to uncertain tax positions of $4.8&amp;#160;million and $4.5&amp;#160;million,
   respectively. Penalties are recognized as part of income tax expense. There were no penalties
   recorded during the six months ended June&amp;#160;30, 2010.
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      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 109
 -Paragraph 136, 172

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 109
 -Paragraph 43, 44, 45, 46, 47, 48, 49

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