Exhibit 12

ERP OPERATING LIMITED PARTNERSHIP
Computation of Ratio of Earnings to Combined Fixed Charges

	03/31/03		03/31/02		12/31/02			12/31/01		12/31/00		12/31/99		12/31/98
Income before allocation to Minority Interests, income (loss) from investments in unconsolidated entities, net gain on sales of unconsolidated entities and discontinued operations	$	72,165	$	89,462	$	328,905		$	393,120	$	360,878	$	302,673	$	234,920
Interest and other financing costs	80,809		84,331		337,489			352,903		363,851		328,459		243,531
Amortization of deferred financing costs	1,408		1,385		5,748			5,818		5,432		4,024		2,724
Income (loss) from investments in unconsolidated entities	107		226		(3,698		)	3,772		2,309		3,850		1,192
Earnings before combined fixed charges and preferred distributions	154,489		175,404		668,444			755,613		732,470		639,006		482,367
Preferred distributions	24,180		24,525		97,151			106,119		111,941		113,196		92,917
Earnings before combined fixed charges	$	130,309	$	150,879	$	571,293		$	649,494	$	620,529	$	525,810	$	389,450
Interest and other financing costs	$	80,809	$	84,331	$	337,489		$	352,903	$	363,851	$	328,459	$	243,531
Amortization of deferred financing costs	1,408		1,385		5,748			5,818		5,432		4,024		2,724
Interest capitalized for real estate and unconsolidated entities under development	5,437		5,884		27,167			28,174		17,650		8,134		1,620
Total combined fixed charges	87,654		91,600		370,404			386,895		386,933		340,617		247,875
Preferred distributions	24,180		24,525		97,151			106,119		111,941		113,196		92,917
Total combined fixed charges and preferred distributions	$	111,834	$	116,125	$	467,555		$	493,014	$	498,874	$	453,813	$	340,792
Ratio of earnings before combined fixed charges to total combined fixed charges	1.49		1.65		1.54			1.68		1.60		1.54		1.57
Ratio of earnings before combined fixed charges and preferred distributions to total combined fixed charges and preferred distributions	1.38		1.51		1.43			1.53		1.47		1.41		1.42