At June 30, 2012, our unsecured debt consisted of $12.3 billion of senior unsecured notes of the Operating Partnership, $1.8 billion outstanding under our $4.0 billion unsecured revolving credit facility, or Credit Facility, and $278.3 million outstanding under our $2.0 billion supplemental unsecured revolving credit facility, or Supplemental Facility. The June 30, 2012 balance on the Credit Facility included $1.1 billion (U.S. dollar equivalent) of Euro-denominated borrowings and the entire balance on the Supplemental Facility on such date consisted of Yen-denominated borrowings, both of which are designated as net investment hedges of our international investments.

On June 30, 2012, we had an aggregate available borrowing capacity of $3.9 billion under the two credit facilities. The maximum outstanding balance of the credit facilities during the six months ended June 30, 2012 was $3.1 billion and the weighted average outstanding balance was $1.6 billion. Letters of credit of $38.9 million were outstanding under the Credit Facility as of June 30, 2012.

The Credit Facility's initial borrowing capacity of $4.0 billion can be increased at our option to $5.0 billion during its term. The Credit Facility will initially mature on October 30, 2015 and can be extended for an additional year at our sole option. The base interest rate on the Credit Facility is LIBOR plus 100 basis points with an additional facility fee of 15 basis points. In addition, the Credit Facility provides for a money market competitive bid option program that allows us to hold auctions to achieve lower pricing for short-term borrowings. The Credit Facility also includes a $2.0 billion multi-currency tranche.

On June 1, 2012, we entered into a Supplemental Facility with an initial borrowing capacity of $2.0 billion which can be increased at our option to $2.5 billion during its term. The Supplemental Facility will initially mature on June 30, 2016 and can be extended for an additional year at our sole option. The base interest rate on the Supplemental Facility is LIBOR plus 100 basis points with an additional facility fee of 15 basis points. Like the Credit Facility, the Supplemental Facility provides for a money market competitive bid option program and allows for multi-currency borrowings. During the second quarter of 2012, we rolled $285.0 million (USD equivalent) of yen-denominated borrowings under the Credit Facility to the Supplemental Facility.

On March 13, 2012, the Operating Partnership issued $600.0 million of senior unsecured notes at a fixed interest rate of 2.15% with a maturity date of September 2017, $600.0 million of senior unsecured notes at a fixed interest rate of 3.375% with a maturity date of March 2022, and $550.0 million of senior unsecured notes at a fixed interest rate of 4.75% with a maturity date of March 2042. Proceeds from the unsecured notes offerings were used to fund a portion of the cost of the acquisition of our equity stake in Klépierre and the Mills transaction.

During the six months ended June 30, 2012, we redeemed at par $124.9 million of senior unsecured notes with fixed rates ranging from 5.75% to 6.88%.

On November 1, 2011, we entered into a $900.0 million unsecured term loan. We drew $160.0 million on the term loan in the first quarter of 2012. In the second quarter of 2012, we repaid the outstanding balance in full and terminated the term loan.

Total secured indebtedness was $8.0 billion and $6.8 billion at June 30, 2012 and December 31, 2011, respectively. During the six months ended June 30, 2012, we repaid $427.8 million in mortgage loans with a weighted average interest rate of 3.17%, unencumbering seven properties, and repaid the outstanding balance of a $735.0 million secured term loan in full.

As a result of the acquisition of additional interests in properties in the Mills transaction in March 2012, as further discussed in Note 5, we consolidated nine properties encumbered by property-level mortgage debt totaling $2.6 billion. This property-level mortgage debt was previously presented as debt of our unconsolidated entities. We and our joint venture partner had equal ownership in these properties prior to the transaction.

Our unsecured debt agreements contain financial covenants and other non-financial covenants. If we were to fail to comply with these covenants, after the expiration of the applicable cure periods, the debt maturity could be accelerated or other remedies could be sought by the lender including adjustments to the applicable interest rate. As of June 30, 2012, we are in compliance with all covenants of our unsecured debt.

At June 30, 2012, we or our subsidiaries are the borrowers under 90 non-recourse mortgage notes secured by mortgages on 90 properties, including 8 separate pools of cross-defaulted and cross-collateralized mortgages encumbering a total of 38 properties. Under these cross-default provisions, a default under any mortgage included in the cross-defaulted pool may constitute a default under all mortgages within that pool and may lead to acceleration of the indebtedness due on each property within the pool. Certain of our secured debt contain financial and other non-financial covenants which are specific to the properties which serve as collateral for that debt. If the borrower fails to comply with these covenants, the lender could accelerate the debt and enforce its right against their collateral. At June 30, 2012, the applicable borrowers under these non-recourse mortgage notes were in compliance with all covenants where non-compliance individually, or giving effect to applicable cross-default provisions in the aggregate, could have a material adverse effect on our financial condition, results of operations or cash flows.

The carrying value of our variable-rate mortgages and other loans approximates their fair values. We estimate the fair values of consolidated fixed-rate mortgages using cash flows discounted at current borrowing rates and other indebtedness using cash flows discounted at current market rates. We estimate the fair values of consolidated fixed-rate unsecured notes using quoted market prices, or, if no quoted market prices are available, we use quoted market prices for securities with similar terms and maturities. The book value of our consolidated fixed-rate mortgages and other indebtedness was $19.8 billion and $15.9 billion as of June 30, 2012 and December 31, 2011, respectively. The fair values of these financial instruments and the related discount rate assumptions as of June 30, 2012 and December 31, 2011 are summarized as follows:

	June 30, 2012		December 31, 2011

Fair value of fixed-rate mortgages and other indebtedness	$	22,065	$17,905
Weighted average discount rates assumed in calculation of fair value for fixed-rate mortgages		3.51%	3.60%