<?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>008110 - Disclosure - Derivatives (Tables)</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>9/1/2010 - 2/28/2011
USD ($)

USD ($) / shares
</KeyName><CurrencySymbol>$</CurrencySymbol><contextRef><ContextID>c00053</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0000104207</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2010-09-01T00:00:00</PeriodStartDate><PeriodEndDate>2011-02-28T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS><UnitProperty><UnitID>u000</UnitID><UnitType>Standard</UnitType><StandardMeasure><MeasureSchema>http://www.xbrl.org/2003/iso4217</MeasureSchema><MeasureValue>USD</MeasureValue><MeasureNamespace>iso4217</MeasureNamespace></StandardMeasure><Scale>0</Scale></UnitProperty><UnitProperty><UnitID>u003</UnitID><UnitType>Standard</UnitType><StandardMeasure><MeasureSchema>http://www.xbrl.org/2003/instance</MeasureSchema><MeasureValue>pure</MeasureValue><MeasureNamespace>xbrli</MeasureNamespace></StandardMeasure><Scale>0</Scale></UnitProperty><UnitProperty><UnitID>u001</UnitID><UnitType>Standard</UnitType><StandardMeasure><MeasureSchema>http://www.xbrl.org/2003/instance</MeasureSchema><MeasureValue>shares</MeasureValue><MeasureNamespace>xbrli</MeasureNamespace></StandardMeasure><Scale>0</Scale></UnitProperty><UnitProperty><UnitID>u002</UnitID><UnitType>Divide</UnitType><NumeratorMeasure><MeasureSchema>http://www.xbrl.org/2003/iso4217</MeasureSchema><MeasureValue>USD</MeasureValue><MeasureNamespace>iso4217</MeasureNamespace></NumeratorMeasure><DenominatorMeasure><MeasureSchema>http://www.xbrl.org/2003/instance</MeasureSchema><MeasureValue>shares</MeasureValue><MeasureNamespace>xbrli</MeasureNamespace></DenominatorMeasure><Scale>0</Scale></UnitProperty></UPS><CurrencyCode>USD</CurrencyCode><OriginalCurrencyCode>USD</OriginalCurrencyCode></MCU><CurrencySymbol>$</CurrencySymbol><Labels><Label Id="1" Label="6 Months Ended" /><Label Id="2" Label="Feb. 28, 2011" /></Labels></Column></Columns><Rows><Row><Id>2</Id><IsAbstractGroupTitle>true</IsAbstractGroupTitle><Level>0</Level><ElementName>us-gaap_StatementOfFinancialPositionAbstract</ElementName><ElementPrefix>us-gaap</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><ShortDefinition>No definition available.</ShortDefinition><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsSubReportEnd>false</IsSubReportEnd><IsCalendarTitle>false</IsCalendarTitle><IsTuple>false</IsTuple><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole /><FootnoteIndexer /><Cells><Cell><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><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>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>No definition available.</ElementDefenition><IsTotalLabel>false</IsTotalLabel><IsEPS>false</IsEPS><Label>Statement of Financial Position [Abstract]</Label></Row><Row><Id>3</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><Level>0</Level><ElementName>wag_NotionalAmountsOfDerivativeInstrumentsOutstandingTextBlock</ElementName><ElementPrefix>wag</ElementPrefix><IsBaseElement>false</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><ShortDefinition>This table presents the notional amounts of derivative instruments outstanding at period end.</ShortDefinition><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsSubReportEnd>false</IsSubReportEnd><IsCalendarTitle>false</IsCalendarTitle><IsTuple>false</IsTuple><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terselabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;The notional amounts of derivative instruments outstanding as of February 28, 2011, August 31, 2010 and February 28, 2010 were as follows (In millions):&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div align="left"&gt;&lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="46%"&gt;&lt;tr&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="62%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160; &lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; BORDER-BOTTOM: black 1px solid" valign="bottom" width="29%" colspan="2"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Notional Amount&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td valign="bottom" align="left" width="62%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Derivatives designated as hedges:&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="29%" colspan="2"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="bottom" align="left" width="62%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Interest rate swaps&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="28%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;1,300&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;</NonNumbericText><NonNumericTextHeader>The notional amounts of derivative instruments outstanding as of February 28, 2011, August 31, 2010 and February 28, 2010 were as follows (In millions):&amp;#160;</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 table presents the notional amounts of derivative instruments outstanding at period end.</ElementDefenition><ElementReferences>No authoritative reference available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><IsEPS>false</IsEPS><Label>Notional amounts of derivative instruments outstanding</Label></Row><Row><Id>4</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><Level>0</Level><ElementName>us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock</ElementName><ElementPrefix>us-gaap</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><ShortDefinition>No definition available.</ShortDefinition><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsSubReportEnd>false</IsSubReportEnd><IsCalendarTitle>false</IsCalendarTitle><IsTuple>false</IsTuple><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole /><FootnoteIndexer /><Cells><Cell><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"&gt;The fair value and balance sheet presentation of derivative instruments at February 28, 2011, August 31, 2010 and February 28, 2010, were as follows (In millions):&lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div align="left"&gt;&lt;table style="FONT-SIZE: 10pt; FONT-FAMILY: times new roman" cellspacing="0" cellpadding="0" width="90%"&gt;&lt;tr&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="25%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160; &lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; BORDER-BOTTOM: black 1px solid" valign="bottom" width="31%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Location in Consolidated Condensed Balance Sheet&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; BORDER-BOTTOM: black 1px solid" valign="bottom" width="9%" colspan="2"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;February 28, &lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;2011&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; BORDER-BOTTOM: black 1px solid" valign="bottom" width="9%" colspan="2"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;August 31, &lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;2010&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; BORDER-BOTTOM: black 1px solid" valign="bottom" width="9%" colspan="2"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;February 28, &lt;/font&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;2010&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td style="BORDER-TOP: medium none; PADDING-BOTTOM: 1px; TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr&gt;&lt;td valign="bottom" align="left" width="25%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Asset derivatives designated as hedges:&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="31%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160; &lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="9%" colspan="2"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="9%" colspan="2"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="9%" colspan="2"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="bottom" align="left" width="25%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Interest rate swaps&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="31%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Other non-current assets&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;38&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;44&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;-&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="white"&gt;&lt;td valign="bottom" align="left" width="25%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Liability derivatives designated as hedges:&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="31%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160; &lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; 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FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="bottom" align="left" width="25%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Interest rate swaps&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="31%"&gt;&lt;div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;Other non-current liabilities&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;-&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;-&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;$&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: right" valign="bottom" width="8%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;1&lt;/font&gt;&lt;/td&gt;&lt;td style="TEXT-ALIGN: left" valign="bottom" nowrap="nowrap" width="1%"&gt;&lt;font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: times new roman"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;div style="DISPLAY: block; TEXT-INDENT: 0pt"&gt;&lt;br /&gt;&lt;/div&gt;</NonNumbericText><NonNumericTextHeader>The fair value and balance sheet presentation of derivative instruments at February 28, 2011, August 31, 2010 and February 28, 2010, were as follows (In</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 can be used as an alternative for disclosing the entity's tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position as a single block of text.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 133
 -Paragraph 205G

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 133
 -Paragraph 44C
 -Subparagraph a

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