
5.	DEBT

Non-Bank Debt

In March 2012, we exercised the call provisions on our Series 1997 5.6%, Series 1998 5.6%, Series 1999 5.7%, Series 2001 6.65%, and Series 1997A 5.45% industrial revenue bonds, which were redeemed on May 3, 2012 for $108 million, or 100 percent of their outstanding stated values.

In April 2012, we made scheduled debt repayments of $4 million related to our Series 1997A 5.45% industrial revenue bonds and $750 million related to our 6.875% notes.

During the three months ended March 31, 2011, the following activity occurred:


•	in February 2011, we made a scheduled debt repayment of $210 million related to our 6.75% senior notes; and


•	in February 2011, we paid $300 million to acquire the Gulf Opportunity Zone Revenue Bonds Series 2010 (GO Zone Bonds), which were subject to mandatory tender. We expect to hold the GO Zone Bonds for our own account until conditions permit the remarketing of these bonds at an interest rate acceptable to us.

Bank Debt and Credit Facilities

We have a $3 billion revolving credit facility (the Revolver) that has a maturity date of December 2016. The Revolver has certain restrictive covenants, including a maximum debt-to-capitalization ratio of 60 percent. As of March 31, 2012 and December 31, 2011, our debt-to-capitalization ratios, calculated in accordance with the terms of the Revolver, were 27 percent and 29 percent, respectively. We believe that we will remain in compliance with this covenant.

In addition to the Revolver, one of our Canadian subsidiaries has a committed revolving credit facility under which it may borrow and obtain letters of credit up to C$115 million.

During the three months ended March 31, 2012 and 2011, we had no borrowings or repayments under our Revolver or the Canadian revolving credit facility. As of March 31, 2012 and December 31, 2011, we had no borrowings outstanding under the Revolver or the Canadian revolving credit facility.

We had outstanding letters of credit under our committed lines of credit as follows (in millions):



				Amounts Outstanding
	Borrowing Capacity		Expiration	March 31, 2012		December 31, 2011
Letter of credit facilities	$	500	June 2012	$	500	$	300
Revolver	$	3,000	December 2016	$	153	$	119
Canadian revolving credit facility	C$	115	December 2012	C$	20	C$	20

As of March 31, 2012 and December 31, 2011, we had $456 million and $391 million, respectively, of letters of credit outstanding under our uncommitted short-term bank credit facilities.

Accounts Receivable Sales Facility

We have an accounts receivable sales facility with a group of third-party entities and financial institutions to sell on a revolving basis up to $1 billion of eligible trade receivables. The facility matures in June 2012. Proceeds from the sale of receivables under this facility are reflected as debt. Changes in the amounts outstanding under our accounts receivable sales facility were as follows (in millions):



	Three Months Ended March 31,
	2012			2011
Balance as of beginning of period	$	250		$	100
Proceeds from the sale of receivables	—			—
Repayments	(150		)	—
Balance as of end of period	$	100		$	100

In late April 2012, we sold $850 million of eligible receivables to the third-party entities and financial institutions under this facility, and we repaid $500 million on May 4, 2012.

Capitalized Interest

For the three months ended March 31, 2012 and 2011, capitalized interest was $52 million and $27 million, respectively.