Prospectus excerpt:  We are offering to the public 12,000,000 of our 5.70% Series K Cumulative Redeemable Preferred Shares of Beneficial Interest, liquidation preference $25.00 per share, which we refer to as the "Series K Preferred Shares".

Dividends on the Series K Preferred Shares will be cumulative from the date of original issue of this series and payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year, commencing on October 1, 2012, at the rate of 5.70% of the liquidation preference per annum, or $1.425 per Series K Preferred Share per annum.

Except in instances relating to preservation of our status as a real estate investment trust, the Series K Preferred Shares are not redeemable until July 18, 2017. On and after July 18, 2017, we may redeem the Series K Preferred Shares in whole at any time or in part from time to time at a redemption price of $25.00 per share, plus any accrued and unpaid dividends through the date of redemption. The Series K Preferred Shares have no maturity date and will remain outstanding indefinitely unless redeemed.