**Exhibit12**

 

**ERP OPERATING LIMITED PARTNERSHIP**

**Computation of Ratio of Earnings to Combined FixedCharges**

 

 
| ** **                                                                                                                                    | ** ** | **09/30/04** | ** **  | **09/30/03** | ** ** | **12/31/03** | ** ** | **12/31/02** | ** **  | **12/31/01** | ** ** | **12/31/00** | ** ** | **12/31/99** | ** **  |
|-----------------------------------------------------------------------------------------------------------------------------------------------|------------|--------------|-------------|--------------|------------|--------------|------------|--------------|-------------|--------------|------------|--------------|------------|--------------|-------------|
| Income from continuing operations                                                                                                             |       | $            | 148,145     |         | $          | 179,676      |       | $            | 229,660     |         | $          | 255,256      |       | $            | 313,508     |   | $ | 279,660 |   | $ | 233,630 |   |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| Interest expense incurred, net                                                                                                                |       | 252,267      |        | 243,579      |       | 324,652      |       | 330,287      |        | 341,505      |       | 353,675      |       | 316,060      |        |
| Amortization of deferred financing costs                                                                                                      |       | 5,062        |        | 3,905        |       | 5,981        |       | 5,576        |        | 4,901        |       | 4,949        |       | 3,787        |        |
| ** **                                                                                                                                    | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  |
| **Earnings before combined fixed charges and  preferred distributions**                                                                       | ** ** | **405,474**  | ** **  | **427,160**  | ** ** | **560,293**  | ** ** | **591,119**  | ** **  | **659,914**  | ** ** | **638,284**  | ** ** | **553,477**  | ** **  |
| ** **                                                                                                                                    | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  |
| Preferred distributions                                                                                                                       |       | 55,896       |        | 73,115       |       | 96,971       |       | 97,151       |        | 106,119      |       | 111,941      |       | 113,196      |        |
| Premium on redemption of preference  units/interests                                                                                          |       | 1,117        |        | —       |       | 20,237       |       | —       |        | 5,324        |       | —       |       | —       |        |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| **Earnings before combined fixed charges**                                                                                                    | ** ** | **$**        | **348,461** | ** **   | **$**      | **354,045**  | ** ** | **$**        | **443,085** | ** **   | **$**      | **493,968**  | ** ** | **$**        | **548,471** | ** ** | **$** | **526,343** | ** ** | **$** | **440,281** | ** ** |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| Interest expense incurred, net                                                                                                                |       | $            | 252,267     |         | $          | 243,579      |       | $            | 324,652     |         | $          | 330,287      |       | $            | 341,505     |   | $ | 353,675 |   | $ | 316,060 |   |
| Amortization of deferred financing costs                                                                                                      |       | 5,062        |        | 3,905        |       | 5,981        |       | 5,576        |        | 4,901        |       | 4,949        |       | 3,787        |        |
| Interest capitalized for real estate and unconsolidated  entities under development                                                           |       | 10,277       |        | 16,013       |       | 20,647       |       | 27,167       |        | 28,174       |       | 17,650       |       | 8,134        |        |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| **Total combined fixed charges**                                                                                                              | ** ** | **267,606**  | ** **  | **263,497**  | ** ** | **351,280**  | ** ** | **363,030**  | ** **  | **374,580**  | ** ** | **376,274**  | ** ** | **327,981**  | ** **  |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| Preferred distributions                                                                                                                       |       | 55,896       |        | 73,115       |       | 96,971       |       | 97,151       |        | 106,119      |       | 111,941      |       | 113,196      |        |
| Premium on redemption of preference  units/interests                                                                                          |       | 1,117        |        | —       |       | 20,237       |       | —       |        | 5,324        |       | —       |       | —       |        |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| **Total combined fixed charges and preferred distributions**                                                                                  | ** ** | **$**        | **324,619** | ** **   | **$**      | **336,612**  | ** ** | **$**        | **468,488** | ** **   | **$**      | **460,181**  | ** ** | **$**        | **486,023** | ** ** | **$** | **488,215** | ** ** | **$** | **441,177** | ** ** |
|                                                                                                                                          |       |         |        |         |       |         |       |         |        |         |       |         |       |         |        |
| **Ratio of earnings before combined fixed charges  to total combined fixed charges**                                                          | ** ** | **1.30**     | ** **  | **1.34**     | ** ** | **1.26**     | ** ** | **1.36**     | ** **  | **1.46**     | ** ** | **1.40**     | ** ** | **1.34**     | ** **  |
| ** **                                                                                                                                    | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  | ** **   | ** ** | ** **   | ** ** | ** **   | ** **  |
| **Ratio of earnings before combined fixed charges  and preferred distributions to total combined fixed charges and preferred  distributions** | ** ** | **1.25**     | ** **  | **1.27**     | ** ** | **1.20**     | ** ** | **1.28**     | ** **  | **1.36**     | ** ** | **1.31**     | ** ** | **1.25**     | ** **  |

 

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