CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME OF ERP OPERATING LIMITED PARTNERSHIP (Unaudited) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive income (loss):
Net income	$ 112,977	$ 29,826	$ 827,796	$ 97,771
Other comprehensive (loss) - derivative instruments:
Unrealized holding (losses) arising during the period	(105,248)	(37,726)	(130,367)	(123,472)
Accumulated other comprehensive income	951	914	2,842	2,379
Other comprehensive income (loss) - other instruments:
Unrealized holding gains (losses) arising during the period	(182)	14	311	(52)
Other comprehensive (loss)	(104,479)	(36,798)	(127,214)	(121,145)
Comprehensive income (loss)	8,498	(6,972)	700,582	(23,374)
Comprehensive income (loss) attributable to controlling interests	3,369	(8,015)	663,889	(26,918)
OPERATING PARTNERSHIP
Comprehensive income (loss):
Net income	112,977	29,826	827,796	97,771
Other comprehensive (loss) - derivative instruments:
Unrealized holding (losses) arising during the period	(105,248)	(37,726)	(130,367)	(123,472)
Accumulated other comprehensive income	951	914	2,842	2,379
Other comprehensive income (loss) - other instruments:
Unrealized holding gains (losses) arising during the period	(182)	14	311	(52)
Other comprehensive (loss)	(104,479)	(36,798)	(127,214)	(121,145)
Comprehensive income (loss)	8,498	(6,972)	700,582	(23,374)
Comprehensive (income) loss attributable to Noncontrolling Interests - Partially Owned Properties	(387)	188	(418)	623
Comprehensive income (loss) attributable to controlling interests	$ 8,111	$ (6,784)	$ 700,164	$ (22,751)

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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