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   &lt;!-- Begin Block Tagged Note 7 - us-gaap:DebtDisclosureTextBlock--&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;7. Debt&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;Total debt, including the current portion of long-term debt, consisted of the following:
   &lt;/div&gt;
   &lt;div align="center"&gt;
   &lt;table style="font-size: 10pt; text-align: left" cellspacing="0" border="0" cellpadding="0" width="100%"&gt;
   &lt;!-- Begin Table Head --&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td width="76%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="5%"&gt;&amp;#160;&lt;/td&gt;
       &lt;td width="1%"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;As of&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;As of&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;March 31,&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;December 31,&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 8pt" valign="bottom"&gt;
       &lt;td nowrap="nowrap" align="left"&gt;&lt;i&gt;(millions)&lt;/i&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;2011&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td nowrap="nowrap" align="right" colspan="2"&gt;2010&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;!-- End Table Head --&gt;
   &lt;!-- Begin Table Body --&gt;
   &lt;tr style="font-size: 1px"&gt;
       &lt;td colspan="9" align="left" style="border-top: 1px solid #000000"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;6.3% senior notes due 2016
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;500&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;500&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;7.75% senior notes due 2018, net of discount
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;499&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;499&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;8.375% senior notes due 2018
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;350&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;350&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;9.75% senior notes due 2014, net of discount
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;296&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;296&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;10% convertible senior notes due 2018, net of discount
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;382&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;382&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Ship mortgage facility (includes $7&amp;#160;million of current portion of long-term debt)
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;41&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;42&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom" style="background: #cceeff"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Industrial revenue bonds (due 2028 through 2034)
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;239&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="right"&gt;239&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 1px"&gt;
       &lt;td colspan="9" align="left" style="border-top: 1px solid #000000"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr valign="bottom"&gt;
       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Total
   &lt;/div&gt;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;2,307&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;2,308&lt;/td&gt;
       &lt;td&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;tr style="font-size: 1px"&gt;
       &lt;td colspan="9" align="left" style="border-top: 3px double #000000"&gt;&amp;#160;&lt;/td&gt;
   &lt;/tr&gt;
   &lt;!-- End Table Body --&gt;
   &lt;/table&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;CREDIT FACILITY&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   Our credit facility allows for revolving loans and letters of credit (up to $250&amp;#160;million) in
   an aggregate principal amount not to exceed the lesser of (a) $400&amp;#160;million or (b)&amp;#160;a borrowing base
   determined by reference to the trade receivables and inventory of USG and its significant domestic
   subsidiaries. The maximum allowable borrowings may be increased at our request with the agreement
   of the lenders providing increased or new lending commitments, provided that the maximum allowable
   borrowings after giving effect to the increase may not exceed $600&amp;#160;million. The credit facility is
   guaranteed by our significant domestic subsidiaries and secured by their and USG&amp;#8217;s trade
   receivables and inventory. It is available to fund working capital needs and for other general
   corporate purposes.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Borrowings under the credit facility bear interest at a floating rate based on an alternate
   base rate or, at our option, at adjusted LIBOR plus 3.00%. We are also required to pay annual
   facility fees of 0.75% on the entire facility, whether drawn or undrawn, and fees on outstanding
   letters of credit. We have the ability to repay amounts outstanding under the credit agreement at
   any time without prepayment premium or penalty. The credit facility matures on December&amp;#160;21, 2015
   unless terminated earlier in accordance with its terms, including if by May&amp;#160;2, 2014 our 9.75%
   senior notes due in 2014 are not repaid, their payment is not provided for or their maturity has
   not been extended until at least 2016 unless we then have liquidity of at least $500&amp;#160;million.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The credit agreement contains a single financial covenant that would require us to maintain a
   minimum fixed charge coverage ratio of 1.1-to-1.0 if and for so long as the excess of the borrowing
   base over the outstanding borrowings under the credit agreement is less than the greater of (a) $40
   million and (b)&amp;#160;15% of the lesser of (i)&amp;#160;the aggregate revolving commitments at such time and (ii)
   the borrowing base at such time. As of March&amp;#160;31, 2011, our fixed charge coverage ratio was
   (0.13)-to-1. Because we do not currently satisfy the required fixed charge coverage ratio, we must
   maintain borrowing availability of at least $42&amp;#160;million under the credit facility. The credit
   agreement contains other covenants and events of default that are customary for similar agreements
   and may limit our ability to take various actions.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Taking into account the most recent borrowing base calculation delivered under the credit
   facility, which reflects trade receivables and inventory as of March&amp;#160;31, 2011, outstanding letters
   of credit and the current availability requirement of $42&amp;#160;million for the fixed charge coverage
   ratio not to apply, borrowings available under the credit facility were approximately $158&amp;#160;million.
   As of March&amp;#160;31, 2011 and during the quarter then-ended, there were no borrowings under the
   facility. Had there been any borrowings as of that date, the applicable interest rate would have
   been 3.3%. Outstanding letters of credit totaled $83&amp;#160;million as of March&amp;#160;31, 2011.
   &lt;/div&gt;
   &lt;!-- Folio --&gt;
   &lt;!-- /Folio --&gt;
   &lt;/div&gt;
   &lt;!-- PAGEBREAK --&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;SENIOR NOTES&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   We have $300&amp;#160;million in aggregate principal amount of 9.75% senior notes due 2014 that are
   recorded on the condensed consolidated balance sheets at $296&amp;#160;million as of March&amp;#160;31, 2011 and
   December&amp;#160;31, 2010, net of debt discount of $4&amp;#160;million. Our obligations under the notes are
   guaranteed on a senior unsecured basis by certain of our domestic subsidiaries.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We have $350&amp;#160;million in aggregate principal amount of 8.375% senior notes due 2018. Our
   obligations under these notes are guaranteed on a senior unsecured basis by the same domestic
   subsidiaries that have guaranteed the 9.75% senior notes.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We have $500&amp;#160;million of 7.75% senior notes due 2018 that are recorded on the condensed
   consolidated balance sheets at $499&amp;#160;million, net of debt discount of $1&amp;#160;million. The interest rate
   payable on these notes is subject to adjustment from time to time by up to 2% in the aggregate if
   the debt ratings assigned to the notes are upgraded or thereafter downgraded. At our current credit
   ratings, the interest rate on these notes is at the maximum level of 9.75%.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;We also have $500&amp;#160;million of 6.3% senior notes due 2016. The 9.75% senior notes, 8.375% senior
   notes, 7.75% senior notes and 6.3% senior notes are senior unsecured obligations and rank equally
   with all of our other existing and future unsecured senior indebtedness. The indentures governing
   the notes contain events of default, covenants and restrictions that are customary for similar
   transactions, including a limitation on our ability and the ability of certain of our subsidiaries
   to create or incur secured indebtedness.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The 9.75% and 8.375% senior notes contain a provision requiring us to offer to purchase those
   notes at a premium of 101% of their principal amount (plus accrued and unpaid interest) in the
   event of a change in control. The 7.75% and 6.3% senior notes contain a provision requiring us to
   offer to purchase those notes at a premium of 101% of their principal amount (plus accrued and
   unpaid interest) in the event of a change in control and a related downgrade of the rating on the
   notes to below investment grade by both Moody&amp;#8217;s Investors Service and Standard &amp;#038; Poor&amp;#8217;s Financial
   Services LLC.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The 9.75%, 7.75% and 6.3% senior notes contain a provision that allows us to redeem
   the notes in whole at any time, or in part from time to time, at our option, at a redemption price
   equal to the greater of (1)&amp;#160;100% of the principal amount of the notes being redeemed and (2)&amp;#160;the
   sum of the present value of the remaining scheduled payments of principal and interest on the notes
   being redeemed discounted to the redemption date on a semi-annual basis at the applicable U.S.
   Treasury rate plus a spread (as outlined in the respective indentures), plus, in each case, any
   accrued and unpaid interest on the principal amount being redeemed to the redemption date. The
   8.375% senior notes contain a similar provision that allows us to redeem those notes, in whole or
   in part from time to time, at our option, beginning on October&amp;#160;15, 2014 at stated redemption
   prices, plus any accrued and unpaid interest. In addition, we may redeem the 8.375% senior notes in
   whole or in part from time to time, at our option, prior to October&amp;#160;15, 2014 at a redemption price
   equal to 100% of the principal amount of the notes redeemed plus a premium (as specified in the
   supplemental indenture with respect to those notes), plus any accrued and unpaid interest.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;CONVERTIBLE SENIOR NOTES&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   We have $400&amp;#160;million aggregate principal amount of 10% convertible senior notes due 2018 that
   are recorded on the condensed consolidated balance sheets at $382&amp;#160;million as of March&amp;#160;31, 2011 and
   December&amp;#160;31, 2010, net of debt discount of $18&amp;#160;million as a result of an embedded derivative. The
   notes bear cash interest at the rate of 10% per year until maturity, redemption or conversion. The
   notes are initially convertible into 87.7193 shares of our common stock per $1,000 principal amount
   of notes which is equivalent to an initial conversion price of $11.40 per share, or a total of 35.1
   million shares. The notes contain anti-dilution provisions that are customary for convertible notes
   issued in transactions similar to that in which the notes were issued. The notes mature on December
   1, 2018 and are not callable until December&amp;#160;1, 2013, after which we may elect to redeem all or part
   of the notes at stated redemption prices, plus accrued and unpaid interest.
   &lt;/div&gt;
   &lt;!-- Folio --&gt;
   &lt;!-- /Folio --&gt;
   &lt;/div&gt;
   &lt;!-- PAGEBREAK --&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The notes are senior unsecured obligations and rank equally with all of our other existing and
   future unsecured senior indebtedness. The indenture governing the notes contains events of default,
   covenants and restrictions that are customary for similar transactions, including a limitation on
   our ability and the ability of certain of our subsidiaries to create or incur secured indebtedness.
   The notes also contain a provision requiring us to offer to purchase the notes at a premium of 105%
   of their principal amount (plus accrued and unpaid interest) in the event of a change in control or
   the termination of trading of our common stock on a national securities exchange.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;SHIP MORTGAGE FACILITY&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   Our subsidiary, Gypsum Transportation Limited, or GTL, has a secured loan facility agreement
   with DVB Bank SE, as lender, agent and security trustee. Both advances provided for under the
   secured loan facility have been drawn, and the total outstanding loan balances under the facility
   were $41&amp;#160;million as of March&amp;#160;31, 2011 and $42&amp;#160;million as of December&amp;#160;31, 2010. Of the total amounts
   outstanding as of March&amp;#160;31, 2011 and December&amp;#160;31, 2010, $7&amp;#160;million was classified as current
   portion of long-term debt on our condensed consolidated balance sheets.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The loan balance under the secured loan facility bears interest at a floating rate based on
   LIBOR plus a margin of 1.65%. The interest rate was 2.31% as of March&amp;#160;31, 2011. Each advance is
   repayable in quarterly installments in amounts determined in accordance with the secured loan
   facility agreement, with the balance of each advance repayable eight years after the date it was
   advanced, or October&amp;#160;31, 2016 and May&amp;#160;22, 2017. The secured loan facility agreement contains
   affirmative and negative covenants affecting GTL and certain customary events of default. GTL has
   granted DVB Bank SE a security interest in the Gypsum Centennial and Gypsum Integrity ships and
   related insurance, contract, account and other rights as security for borrowings under the secured
   loan facility. USG Corporation has guaranteed the obligations of GTL under the secured loan
   facility and has agreed to maintain liquidity of at least $175&amp;#160;million.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;CGC CREDIT FACILITY&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   Our Canadian subsidiary, CGC Inc., or CGC, has a Can. $30&amp;#160;million credit agreement with The
   Toronto-Dominion Bank. The credit agreement allows for revolving loans and letters of credit (up to
   Can. $3&amp;#160;million in aggregate) in an aggregate principal amount not to exceed Can. $30&amp;#160;million. The
   credit agreement is available for the general corporate purposes of CGC, excluding hostile
   acquisitions. The credit agreement is secured by a general security interest in substantially all
   of CGC&amp;#8217;s assets other than intellectual property.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Revolving loans under the agreement may be made in Canadian dollars or U.S.
   dollars. Revolving loans made in Canadian dollars bear interest at a floating rate based on the
   prime rate plus 1.50% or the Bankers&amp;#8217; Acceptance Discount Rate plus 3.00%, at the option of CGC.
   Revolving loans made in U.S. dollars bear interest at a floating rate based upon a base rate plus
   1.50% or the LIBOR rate plus 3.00%, at the option of CGC. CGC may prepay the revolving loans at its
   discretion without premium or penalty and may be required to repay revolving loans under certain
   circumstances. The credit agreement matures on June&amp;#160;1, 2012, unless terminated earlier in
   accordance with its terms. The credit agreement contains customary representations and warranties,
   affirmative and negative covenants that may limit CGC&amp;#8217;s ability to take certain actions and events
   of default. Borrowings under the credit agreement are subject to acceleration upon the occurrence
   of an event of default.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;As of March&amp;#160;31, 2011 and during the quarter then ended, there were no borrowings outstanding
   under this credit agreement. Had there been any borrowings as of that date, the applicable interest
   rate would have been 4.3%. As of March&amp;#160;31, 2011, outstanding letters of credit totaled Can. $0.4
   million. The U.S. dollar equivalent of borrowings available under this agreement as of March&amp;#160;31,
   2011 was $31&amp;#160;million.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;INDUSTRIAL REVENUE BONDS&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   Our $239&amp;#160;million of industrial revenue bonds have fixed interest rates ranging from 5.5% to
   6.4%. The weighted average rate of interest on our industrial revenue bonds is 5.875%. The average
   maturity of these bonds is 20&amp;#160;years.
   &lt;/div&gt;
   &lt;!-- Folio --&gt;
   &lt;!-- /Folio --&gt;
   &lt;/div&gt;
   &lt;!-- PAGEBREAK --&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif"&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;OTHER INFORMATION&lt;br /&gt;&lt;br style="font-size: 6pt" /&gt;
   The fair value of our debt was $2.677&amp;#160;billion as of March&amp;#160;31, 2011 and $2.564&amp;#160;billion as of
   December&amp;#160;31, 2010. The fair value was based on quoted market prices of our debt or, where quoted
   market prices were not available, on quoted market prices of instruments with similar terms and
   maturities or internal valuation models.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;As of March&amp;#160;31, 2011, we were in compliance with the covenants contained in our credit
   facilities.
   &lt;/div&gt;
   &lt;/div&gt;
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 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 02
 -Paragraph 19, 20, 22
 -Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 129
 -Paragraph 2, 4

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