<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><Version>2.2.0.25</Version><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><ReportLongName>11101 - Disclosure - Net Interest Expense</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelColumn>false</LabelColumn><CurrencyCode>USD</CurrencyCode><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName>1/31/2010 - 1/29/2011
USD ($)

USD ($) / shares
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&lt;/i&gt;&lt;/font&gt;
&lt;div&gt;

&lt;p style="font-size: 12pt; margin: 9pt 0in 0pt; font-family: 'Times New Roman','serif';"&gt;&lt;b&gt;10) &lt;/b&gt;&lt;b&gt;&lt;u&gt;Net Interest Expense &lt;/u&gt;&lt;/b&gt;&lt;/p&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 9pt;"&gt; &lt;/font&gt;&amp;nbsp;&lt;/p&gt;

&lt;div&gt;

&lt;div align="center"&gt;

&lt;table class="MsoNormalTable" style="font-size: 11pt; width: 101.58%; font-family: 'Calibri','sans-serif'; border-collapse: collapse;" cellspacing="0" cellpadding="0" width="101%" border="0"&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="279"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;i&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;($ in millions)&lt;/font&gt;&lt;/i&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" width="126"&gt;

&lt;p class="MsoNormal" style="font-size: 12pt; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; text-align: center;" align="center"&gt;&lt;b&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;2010&lt;/font&gt;&lt;/b&gt; &lt;/p&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;p class="MsoNormal" style="font-size: 12pt; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; text-align: center;" align="center"&gt;&lt;b&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;2009&lt;/font&gt;&lt;/b&gt; &lt;/p&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;p class="MsoNormal" style="font-size: 12pt; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; text-align: center;" align="center"&gt;&lt;b&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;2008&lt;/font&gt;&lt;/b&gt; &lt;/p&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="top" width="279"&gt;

&lt;p style="font-size: 12pt; margin-left: 12pt; text-indent: -12pt; margin-right: 0in; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;Long-term debt&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="126"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 223 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 255 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &amp;nbsp;&amp;nbsp;268 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="top" width="279"&gt;

&lt;p style="font-size: 12pt; margin-left: 12pt; text-indent: -12pt; margin-right: 0in; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;Short-term investments&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="126"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; (2)&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; (3)&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; (32 )&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="top" width="279"&gt;

&lt;p style="font-size: 12pt; margin-left: 12pt; text-indent: -12pt; margin-right: 0in; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;Other, net&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="126"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 10&lt;sup&gt;(1)&lt;/sup&gt;&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 8&lt;sup&gt;(1)&lt;/sup&gt;&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; (11 )&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="bottom" width="279"&gt;

&lt;p class="la2" style="font-size: 4pt; margin: 0in 0in 0pt; line-height: 2pt; font-family: 'Times New Roman','serif';"&gt;&amp;nbsp;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" width="126"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: left;" align="left"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: left;" align="left"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 1pt solid; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrdsinglerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="top" width="279"&gt;

&lt;p style="font-size: 12pt; margin-left: 12pt; text-indent: -12pt; margin-right: 0in; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;Total&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="126"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 231&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 260 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" nowrap="nowrap" width="139"&gt;

&lt;p style="font-size: 12pt; margin: 0in 0in 0.75pt; font-family: 'Times New Roman','serif';"&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;$&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 225 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 209.55pt; padding-top: 0in;" valign="bottom" width="279"&gt;

&lt;p class="la2" style="font-size: 4pt; margin: 0in 0in 0pt; line-height: 2pt; font-family: 'Times New Roman','serif';"&gt;&amp;nbsp;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 94.15pt; padding-top: 0in;" valign="bottom" width="126"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 3px double; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrddoublerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 3px double; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrddoublerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;
&lt;td style="padding-right: 0in; padding-left: 0.1in; padding-bottom: 0in; width: 104.15pt; padding-top: 0in;" valign="bottom" width="139"&gt;

&lt;div style="border-right: medium none; padding-right: 0in; border-top: windowtext 3px double; padding-left: 0in; padding-bottom: 0in; border-left: medium none; padding-top: 1pt; border-bottom: medium none;"&gt;

&lt;p class="rrddoublerule" style="border-right: medium none; padding-right: 0in; border-top: medium none; padding-left: 0in; font-size: 4pt; padding-bottom: 0in; margin: 1pt 0in 0pt; border-left: medium none; line-height: 1pt; padding-top: 0in; border-bottom: medium none; font-family: 'Times New Roman','serif'; text-align: center;"&gt;&amp;nbsp;&lt;/p&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;

&lt;p style="font-size: 12pt; margin: 9pt 0in 0pt; font-family: 'Times New Roman','serif';"&gt;&lt;i&gt;&lt;font class="_mt" style="font-size: 10pt;"&gt;(1) Reflects increased financing costs due to the Credit Facility and lower levels of capitalized interest due to lower capital expenditures. &lt;/font&gt;&lt;/i&gt;&lt;/p&gt;&lt;/div&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText><NonNumericTextHeader>10) Net Interest Expense

 &amp;nbsp;








($ in millions)


2010



&amp;nbsp;


2009



&amp;nbsp;


2008



&amp;nbsp;


Long-term</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 text block may contain information related to interest income and interest expense for enterprises that derive a significant portion of their revenue from interest collected on investments, loans, and securities.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 04
 -Paragraph 1 - 9
 -Article 9

</ElementReferences><IsTotalLabel>false</IsTotalLabel><IsEPS>false</IsEPS><Label>Net Interest Expense</Label></Row></Rows><Footnotes /><NumberOfCols>1</NumberOfCols><NumberOfRows>1</NumberOfRows><ReportName>Net Interest Expense</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>false</HasCustomUnits><SharesShouldBeRounded>true</SharesShouldBeRounded></InstanceReport>
