NOTES TO CONSOLIDATED FINANCIAL STATEMENTS (Dollars in thousands, except share and per share amounts and where indicated as in millions or billions) 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 $15.9 billion and $14.8 billion  as of December 31, 2011 and 2010, respectively. The fair values of these financial instruments and the related discount rate  assumptions as of December 31 are summarized as follows: Future minimum rentals to be received under non-cancelable tenant operating leases for each of the next five years and  thereafter, excluding tenant reimbursements of operating expenses and percentage rent based on tenant sales volume as of  December 31, 2011 are as follows: Approximately 0.6% of future minimum rents to be received are attributable to leases with an affiliate of a limited partner in  the Operating Partnership. Our Board of Directors is authorized to reclassify excess common stock into one or more additional classes and series of  capital stock, to establish the number of shares in each class or series and to fix the preferences, conversion and other rights,  voting powers, restrictions, limitations as to dividends, and qualifications and terms and conditions of redemption of such class or  series, without any further vote or action by the stockholders. The issuance of additional classes or series of capital stock may have  the effect of delaying, deferring or preventing a change in control of Simon Property without further action of the stockholders. The  ability to issue additional classes or series of capital stock, while providing flexibility in connection with possible acquisitions and  other corporate purposes, could have the effect of making it more difficult for a third party to acquire, or of discouraging a third  party from acquiring, a majority of our outstanding voting stock. Holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of  stockholders, other than for the election of directors. The holders of our Class B common stock have the right to elect up to four  members of the Board of Directors. All 8,000 outstanding shares of the Class B common stock are subject to two voting trusts as  to which Herbert Simon and David Simon are the trustees. Shares of Class B common stock convert automatically into an equal  number of shares of common stock upon the occurrence of certain events and can be converted into shares of common stock at  the option of the holders. 10. EQUITY 9. RENTALS UNDER OPERATING LEASES Fair Value of Financial Instruments 2011 2010 Fair value of fixed-rate mortgages and other indebtedness  $17,905 $16,087 Weighted average discount rates assumed in calculation of fair value for fixed-rate mortgages  3.60% 4.46% 2012 $ 2,273,866 2013 2,049,321 2014 1,833,426 2015 1,575,756 2016 1,328,790 Thereafter 3,445,759 $12,506,918 56 Simon Property Group, Inc.