CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Comprehensive income (loss):
Net income	$ 581,753	$ 10,089	$ 714,819	$ 67,945
Other comprehensive (loss) - derivative instruments:
Unrealized holding (losses) arising during the period	(31,201)	(72,243)	(25,119)	(85,746)
Losses reclassified into earnings from other comprehensive income	935	739	1,891	1,465
Other comprehensive income (loss) - other instruments:
Unrealized holding gains (losses) arising during the period	347	93	493	(66)
Other comprehensive (loss)	(29,919)	(71,411)	(22,735)	(84,347)
Comprehensive income	551,834	(61,322)	692,084	(16,402)
Comprehensive income (loss) attributable to controlling interests	526,005	(61,450)	660,520	(18,903)
OPERATING PARTNERSHIP
Comprehensive income (loss):
Net income	581,753	10,089	714,819	67,945
Other comprehensive (loss) - derivative instruments:
Unrealized holding (losses) arising during the period	(31,201)	(72,243)	(25,119)	(85,746)
Losses reclassified into earnings from other comprehensive income	935	739	1,891	1,465
Other comprehensive income (loss) - other instruments:
Unrealized holding gains (losses) arising during the period	347	93	493	(66)
Other comprehensive (loss)	(29,919)	(71,411)	(22,735)	(84,347)
Comprehensive income	551,834	(61,322)	692,084	(16,402)
Comprehensive (income) loss attributable to Noncontrolling Interests - Partially Owned Properties	(71)	185	(31)	435
Comprehensive income (loss) attributable to controlling interests	$ 551,763	$ (61,137)	$ 692,053	$ (15,967)

The change in equity (net assets) of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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