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USD ($)

USD ($) / shares

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&lt;p style="margin-top: 12px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&lt;b&gt;K. Earnings Per Share&lt;/b&gt; &amp;ndash; Basic earnings per share (EPS) amounts are computed by dividing earnings, after the deduction of preferred stock dividends declared and dividends and undistributed earnings allocated to participating securities, by the average number of common shares outstanding. Diluted EPS amounts assume the issuance of common stock for all potentially dilutive share equivalents outstanding not classified as participating securities. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 12px; margin-bottom: 0px; font-size: 1px;"&gt;&amp;nbsp;&lt;/p&gt;

&lt;p style="margin-top: 0px; text-indent: 32px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;The information used to compute basic and diluted EPS attributable to Alcoa common shareholders was as follows (shares in millions): &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 0px; margin-bottom: 0px; font-size: 12px;"&gt;&amp;nbsp;&lt;/p&gt;

&lt;table border="0" cellspacing="0" cellpadding="0" width="76%" align="center"&gt;
&lt;tr&gt;&lt;td width="82%"&gt; &lt;/td&gt;
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&lt;td&gt; &lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;td valign="bottom" width="6%"&gt; &lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;td&gt; &lt;/td&gt;
&lt;td&gt; &lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="border-bottom: #000000 1px solid;" valign="bottom" colspan="6" align="center"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="1"&gt;&lt;b&gt;First quarter ended&lt;/b&gt;&lt;/font&gt;&lt;br /&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="1"&gt;&lt;b&gt;March&amp;nbsp;31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="border-bottom: #000000 1px solid;" valign="bottom" colspan="2" align="center"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="1"&gt;&lt;b&gt;2011&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="border-bottom: #000000 1px solid;" valign="bottom" colspan="2" align="center"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="1"&gt;&lt;b&gt;2010&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Income (loss) from continuing operations attributable to Alcoa common shareholders&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;309&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;(194&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;)&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Less: preferred stock dividends declared&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-size: 1px;"&gt;&lt;td valign="bottom"&gt; &lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
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&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Income (loss) from continuing operations available to common equity&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;308&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;(195&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;)&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Less: dividends and undistributed earnings allocated to participating securities&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;#8212;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-size: 1px;"&gt;&lt;td valign="bottom"&gt; &lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
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&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Income (loss) from continuing operations available to Alcoa common shareholders &amp;ndash; basic&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;307&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;(195&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;)&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Add: interest expense related to convertible notes&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;8&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;#8212;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-size: 1px;"&gt;&lt;td valign="bottom"&gt; &lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 1px solid;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Income (loss) from continuing operations available to Alcoa common shareholders &amp;ndash; diluted&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;315&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;(195&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;)&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-size: 1px;"&gt;&lt;td valign="bottom"&gt; &lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 3px double;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 3px double;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
&lt;td style="border-top: #000000 3px double;" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
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&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td valign="top"&gt;

&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Average shares outstanding &amp;ndash; basic&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1,052&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1,007&lt;/font&gt;&lt;/td&gt;
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&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Effect of dilutive securities:&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt; &lt;/td&gt;
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&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt; &lt;/td&gt;
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&lt;p style="text-indent: -1em; margin-left: 3em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Stock options&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;9&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;#8212;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
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&lt;p style="text-indent: -1em; margin-left: 3em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Stock and performance awards&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;3&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;#8212;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
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&lt;p style="text-indent: -1em; margin-left: 3em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Convertible notes&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;89&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;#8212;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-size: 1px;"&gt;&lt;td valign="bottom"&gt; &lt;/td&gt;
&lt;td valign="bottom"&gt;&amp;nbsp;&amp;nbsp;&lt;/td&gt;
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&lt;p style="text-indent: -1em; margin-left: 1em;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Average shares outstanding &amp;ndash; diluted&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font class="_mt" size="1"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1,153&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom" nowrap="nowrap"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;&amp;nbsp;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
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&lt;td valign="bottom" align="right"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;1,007&lt;/font&gt;&lt;/td&gt;
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&lt;p style="margin-top: 12px; text-indent: 32px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Participating securities are defined as unvested share-based payment awards that contain nonforfeitable rights to dividends or dividend equivalents (whether paid or unpaid) and are included in the computation of earnings per share pursuant to the two-class method. Prior to January&amp;nbsp;1, 2010, under Alcoa's stock-based compensation programs, certain employees were granted stock and performance awards, which entitle those employees to receive nonforfeitable dividends during the vesting period on a basis equivalent to the dividends paid to holders of Alcoa's common stock. As such, these unvested stock and performance awards met the definition of a participating security. Under the two-class method, all earnings, whether distributed or undistributed, are allocated to each class of common stock and participating securities based on their respective rights to receive dividends. At March&amp;nbsp;31, 2011 and 2010, there were&amp;nbsp;&lt;font class="_mt"&gt;2&lt;/font&gt;&amp;nbsp;million and&amp;nbsp;&lt;font class="_mt"&gt;5&lt;/font&gt;&amp;nbsp;million such participating securities outstanding, respectively. None of the loss from continuing operations in the 2010 first quarter was allocated to these participating securities because these awards do not share in any loss generated by Alcoa. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 12px; text-indent: 32px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Effective January&amp;nbsp;1, 2010, new grants of stock and performance awards do not contain a nonforfeitable right to dividends during the vesting period. As a result, an employee will forfeit the right to dividends accrued on unvested awards if that person does not fulfill their service requirement during the vesting period. As such, these awards are not treated as participating securities in the EPS calculation as the employees no longer have equivalent dividend rights as common shareholders. These awards are included in the EPS calculation utilizing the treasury stock method similar to stock options. At March&amp;nbsp;31, 2011 and 2010, there were&amp;nbsp;&lt;font class="_mt"&gt;8&lt;/font&gt;&amp;nbsp;million and&amp;nbsp;&lt;font class="_mt"&gt;3&lt;/font&gt;&amp;nbsp;million such awards outstanding, respectively. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 12px; text-indent: 32px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;In the first quarter of 2010, basic average shares outstanding and diluted average shares outstanding were the same because the effect of potential shares of common stock was anti-dilutive since Alcoa generated a loss from continuing operations. As a result,&amp;nbsp;&lt;font class="_mt"&gt;89&lt;/font&gt;&amp;nbsp;million share equivalents related to convertible notes were not included in the computation of diluted EPS. Additionally,&amp;nbsp;&lt;font class="_mt"&gt;34&lt;/font&gt;&amp;nbsp;million stock options and&amp;nbsp;&lt;font class="_mt"&gt;3&lt;/font&gt;&amp;nbsp;million stock and performance awards were not included in the computation of diluted EPS. Had Alcoa generated sufficient income from continuing operations in the 2010 first quarter,&amp;nbsp;&lt;font class="_mt"&gt;89&lt;/font&gt;&amp;nbsp;million and&amp;nbsp;&lt;font class="_mt"&gt;7&lt;/font&gt;&amp;nbsp;million potential shares of common stock related to the convertible notes and stock options, respectively, would have been included in diluted average shares outstanding. &lt;/font&gt;&lt;/p&gt;

&lt;p style="margin-top: 12px; text-indent: 32px; margin-bottom: 0px;"&gt;&lt;font style="font-family: Times New Roman;" class="_mt" size="2"&gt;Options to purchase&amp;nbsp;&lt;font class="_mt"&gt;15&lt;/font&gt;&amp;nbsp;million and&amp;nbsp;&lt;font class="_mt"&gt;24&lt;/font&gt;&amp;nbsp;million shares of common stock at a weighted average exercise price of $&lt;font class="_mt"&gt;32.27&lt;/font&gt; and $&lt;font class="_mt"&gt;32.70&lt;/font&gt; per share were outstanding as of March&amp;nbsp;31, 2011 and 2010, respectively, but were not included in the computation of diluted EPS because they were anti-dilutive, as the exercise prices of the options were greater than the average market price of Alcoa's common stock. &lt;/font&gt;&lt;/p&gt; &lt;/div&gt;</NonNumbericText><NonNumericTextHeader>K. Earnings Per Share &amp;ndash; Basic earnings per share (EPS) amounts are computed by dividing earnings, after the deduction of preferred stock dividends</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>This element may be used to capture the complete disclosure pertaining to an entity's earnings per share.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 128
 -Paragraph 40

</ElementReferences><IsTotalLabel>false</IsTotalLabel><IsEPS>false</IsEPS><Label>Earnings Per Share</Label></Row></Rows><Footnotes /><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows><ReportName>Earnings Per Share</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>false</HasCustomUnits><SharesShouldBeRounded>true</SharesShouldBeRounded></InstanceReport>
