2011 Dispositions 2010 Impairment 2009 Impairment 8. INDEBTEDNESS AND DERIVATIVE FINANCIAL INSTRUMENTS 2011 Annual Report 53 In April 2011 we disposed of our interest in an unconsolidated regional mall, resulting in a gain of $7.8 million. This gain is  reported in gain (loss) upon acquisition of controlling interests, and on sale or disposal of assets and interests in unconsolidated  entities, net in the consolidated statements of operations and comprehensive income. In December 2010, we recognized an $8.2 million non-cash impairment charge representing our share of impairment on a  joint venture investment in a property in Italy for which the decline in value below our carrying amount was deemed other-than- temporary. In December 2009 we recognized non-cash impairment charges of $7.6 million representing our share of impairment charges  on joint venture properties. These charges represent adjustments to the carrying value of certain parcels of land and the write-off  of predevelopment costs related to certain projects no longer being pursued. In addition, in December 2009 we recognized $35.1  million of impairment charges for investments in certain unconsolidated entities including one regional mall and two non-retail real  estate assets for which declines in value below our carrying amount were deemed other-than-temporary. Our mortgages and other indebtedness, excluding the impact of derivative instruments, consist of the following as of  December 31: General.  Our unsecured debt contains 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 December 31, 2011, we are in compliance with  all covenants of our unsecured debt. At December 31, 2011, we or our subsidiaries are the borrowers under 89 non-recourse mortgage notes secured by mortgages  on 89 properties, including 10 separate pools of cross-defaulted and cross-collateralized mortgages encumbering a total of 44  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 contains 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 December 31, 2011, the applicable borrowers under these non-recourse mortgage  notes were in compliance with all covenants where non-compliance could individually, or giving effect to applicable cross-default  provisions, have a material adverse effect on our financial condition, results of operations or cash flows. 2011 2010 Fixed-Rate Debt:  Mortgages and other notes, including $54,250 and $31,614 net premiums, respectively.  Weighted average interest and maturity of 6.05% and 4.7 years at December 31, 2011.  $ 5,566,600 $ 5,485,659 Unsecured notes, including $29,178 and $26,586 net discounts, respectively.  Weighted average interest and maturity of 5.76% and 6.8 years at December 31, 2011.  10,640,775 9,985,886 Total Fixed-Rate Debt  16,207,375 15,471,545 Variable-Rate Debt:  Mortgages and other notes, at face value. Weighted average interest and maturity of 1.74% and 0.8 years at December 31, 2011.  1,286,401 1,143,578 Credit Facility (see below)  952,664 858,637 Total Variable-Rate Debt  2,239,065 2,002,215 Total Mortgages and Other Indebtedness  $18,446,440 $ 17,473,760