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&lt;p style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&lt;b&gt;8.&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;INCOME TAX&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
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&lt;p style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The Company's effective income tax rate was 34% and 36% for the three and six months ended June&amp;#160;30, 2012 and 2013, respectively. The increase in effective tax rate when comparing the three- and six-month periods ended June&amp;#160;30, 2012 and 2013 was primarily due to recognition of certain foreign tax credits in the first half of 2012 that were deducted from US&amp;#160;income tax.&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The tax years ended December&amp;#160;31, 2010, 2011 and 2012 remain subject to examination by the Russian and US&amp;#160;tax authorities. The tax years ended December&amp;#160;31, 2008 through 2012 remain subject to examination by the Kazakh tax authorities.&lt;/font&gt;&lt;/p&gt;
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