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        ERP OPERATING LIMITED PARTNERSHIP
             CONSOLIDATED HISTORICAL
        COMPUTATION OF RATIO OF EARNINGS TO COMBINED FIXED CHARGES

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                                                                                              HISTORICAL
                                                                           --------------------------------------------------
                                                                              06/30/01           6/30/00         12/31/00
                                                                           --------------------------------------------------
                                                                                         (Amounts in thousands)
<S>                                                                      <C>                <C>              <C>
Income before allocation to Minority Interests, income
  from investments in unconsolidated entities, net gain
  on sales of real estate, extraordinary items and cummulative
  effect of change in accounting principle                               $        199,172   $       176,057  $       380,613

   Interest and other financing costs                                             190,383           190,263          382,946
   Amortization of deferred financing costs                                         2,810             2,703            5,473
   Income from investments in unconsolidated entities (cash basis)                 11,795             8,913           18,051
                                                                           ---------------    --------------   --------------

EARNINGS BEFORE COMBINED FIXED CHARGES
   AND PREFERRED DISTRIBUTIONS                                                    404,160           377,936          787,083

   Preferred distributions                                                         57,419            55,654          111,941
                                                                           ---------------    --------------   --------------
EARNINGS BEFORE COMBINED FIXED CHARGES                                   $        346,741   $       322,282  $       675,142
                                                                           ===============    ==============   ==============

   Earnings before combined fixed charges and preferred distributions             404,160           377,936          787,083
   Depreciation/amortization                                                      227,802           224,512          451,344
   Non-real estate depreciation                                                    (3,980)           (3,157)         (12,093)
   Depreciation from Unconsolidated and Partially Owned Properties                  4,729              (491)           1,244
   Loss on investment in technology segment                                         6,775                 -            1,000
   Allocation to Minority Interests-Partially Owned Properties                        238              (157)             132
                                                                           ---------------    --------------   --------------

FUNDS FROM OPERATIONS BEFORE COMBINED FIXED
    CHARGES AND PREFERRED DISTRIBUTIONS                                  $        639,724   $       598,643  $     1,228,710
                                                                           ===============    ==============   ==============

 Interest and other financing costs                                      $        190,383   $       190,263  $       382,946
 Amortization of deferred financing costs                                           2,810             2,703            5,473
 Interest capitalized for real estate under construction                            1,408               480            1,325
                                                                           ---------------    --------------   --------------

TOTAL COMBINED FIXED CHARGES                                                      194,601           193,446          389,744

   Preferred distributions                                                         57,419            55,654          111,941
                                                                           ---------------    --------------   --------------
TOTAL COMBINED FIXED CHARGES
   AND PREFERRED DISTRIBUTIONS                                           $        252,020   $       249,100  $       501,685
                                                                           ===============    ==============   ==============

RATIO OF EARNINGS BEFORE COMBINED FIXED CHARGES
    TO TOTAL COMBINED FIXED CHARGES                                                  1.78              1.67             1.73
                                                                           ===============    ==============   ==============

RATIO OF EARNINGS BEFORE COMBINED FIXED CHARGES
    AND PREFERRED DISTRIBUTIONS TO TOTAL COMBINED
    FIXED CHARGES AND PREFERRED DISTRIBUTIONS                                        1.60              1.52             1.57
                                                                           ===============    ==============   ==============

RATIO OF FUNDS FROM OPERATIONS BEFORE COMBINED
    FIXED CHARGES AND PREFERRED DISTRIBUTIONS TO TOTAL
    COMBINED FIXED CHARGES AND PREFERRED
    DISTRIBUTIONS                                                                    2.54              2.40             2.45
                                                                           ===============    ==============   ==============

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                                                                                                 HISTORICAL
                                                                         ----------------------------------------------------------
                                                                             12/31/99         12/31/98         12/31/97    12/31/96
                                                                         ----------------------------------------------------------
                                                                                         (Amounts in thousands)
<S>                                                                      <C>           <C>            <C>              <C>
Income before allocation to Minority Interests, income
  from investments in unconsolidated entities, net gain
  on sales of real estate, extraordinary items and cummulative
  effect of change in accounting principle                               $     319,842   $    251,927   $    176,014   $     97,033

   Interest and other financing costs                                          337,189        246,585        121,324         81,351
   Amortization of deferred financing costs                                      4,084          2,757          2,523          4,242
   Income from investments in unconsolidated entities (cash basis)               7,125          2,039              -              -
                                                                          -------------  -------------  -------------  ------------

EARNINGS BEFORE COMBINED FIXED CHARGES
   AND PREFERRED DISTRIBUTIONS                                                 668,240        503,308        299,861        182,626

   Preferred distributions                                                     113,196         92,917         59,012         29,015
                                                                          -------------  -------------  -------------  ------------
EARNINGS BEFORE COMBINED FIXED CHARGES                                   $     555,044   $     410,391  $    240,849   $    153,611
                                                                          =============  =============  =============  ============

   Earnings before combined fixed charges and preferred distributions          668,240        503,308        299,861        182,626
   Depreciation/amortization                                                   408,688        301,869        156,644         93,253
   Non-real estate depreciation                                                 (7,231)        (5,361)        (3,118)        (2,079)
   Depreciation from Unconsolidated and Partially Owned Properties               1,009            183              -              -
   Loss on investment in technology segment                                          -              -              -              -
   Allocation to Minority Interests-Partially Owned Properties                       -              -              -              -
                                                                          -------------  -------------  -------------  ------------

FUNDS FROM OPERATIONS BEFORE COMBINED FIXED
    CHARGES AND PREFERRED DISTRIBUTIONS                                  $   1,070,706   $    799,999   $    453,387   $    273,800
                                                                          =============  =============  =============  ============

 Interest and other financing costs                                      $     337,189   $    246,585   $    121,324   $     81,351
 Amortization of deferred financing costs                                        4,084          2,757          2,523          4,242
 Interest capitalized for real estate under construction                         1,493          1,620              -              -
                                                                          -------------  -------------  -------------  ------------

TOTAL COMBINED FIXED CHARGES                                                   342,766        250,962        123,847         85,593

   Preferred distributions                                                     113,196         92,917         59,012         29,015
                                                                          -------------  -------------  -------------  ------------
TOTAL COMBINED FIXED CHARGES
   AND PREFERRED DISTRIBUTIONS                                           $     455,962   $    343,879   $    182,859   $    114,608
                                                                          =============  =============  =============  ============

RATIO OF EARNINGS BEFORE COMBINED FIXED CHARGES
    TO TOTAL COMBINED FIXED CHARGES                                               1.62           1.64           1.94           1.79
                                                                          =============  =============  =============  ============

RATIO OF EARNINGS BEFORE COMBINED FIXED CHARGES
    AND PREFERRED DISTRIBUTIONS TO TOTAL COMBINED
    FIXED CHARGES AND PREFERRED DISTRIBUTIONS                                     1.47           1.46           1.64           1.59
                                                                          =============  =============  =============  ============

RATIO OF FUNDS FROM OPERATIONS BEFORE COMBINED
    FIXED CHARGES AND PREFERRED DISTRIBUTIONS TO TOTAL
    COMBINED FIXED CHARGES AND PREFERRED
    DISTRIBUTIONS                                                                 2.35           2.33           2.48           2.39
                                                                          =============  =============  =============  ============
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