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CORPORATE OFFICE PROPERTIES TRUST
SCHEDULE III - REAL ESTATE DEPRECIATION AND AMORTIZATION
DECEMBER 31, 2001
(DOLLARS IN THOUSANDS)
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INITIAL COST
--------------------------------
BUILDING AND LAND
PROPERTY LOCATION BUILDING TYPE ENCUMBRANCES LAND IMPROVEMENTS
- ------------------------------- ----------------------- -------------------- ------------------- ------------- -----------------
751, 753 760, 785 Jolly Road Blue Bell, PA Office 56,047 22,872 88,387
15000 Conference Center Drive Chantilly, VA Office 25,000 9,451 49,517
2730 Hercules Road Annapolis Junction, MD Office 25,593 7,897 31,589
695 Route 46 Fairfield, NJ Office 9,070 3,732 14,927
431 Ridge Road Dayton, NJ Office 11,982 2,782 11,128
7200 Riverwood Drive Columbia, MD Office 8,605 4,085 16,342
6009 - 6011 Oxon Hill Road Oxon Hill, MD Office 9,302 3,432 13,728
6731 Columbia Gtwy Drive Columbia, MD Office 10,396 3,948 14,286
9690 Deereco Road Timonium, MD Office 8,186 3,426 13,705
6950 Columbia Gateway Drive Columbia, MD Office 11,570 3,593 14,258
2721 Technology Drive Annapolis Junction, MD Office 13,740 2,947 14,615
132 National Business Parkway Annapolis Junction, MD Office 12,004 2,917 12,426
429 Ridge Road Dayton, NJ Office 12,617 2,930 11,719
1306 Concourse Drive Linthicum, MD Office 10,181 2,794 11,177
6940 Columbia Gateway Drive Columbia, MD Office 9,476 3,544 9,912
6750 Alexander Bell Drive Columbia, MD Office 9,084 1,263 12,287
375 W. Padonia Road Timonium, MD Office 5,628 2,600 10,401
133 National Business Parkway Annapolis Junction, MD Office 8,151 2,515 10,060
1304 Concourse Drive Linthicum, MD Office 6,980 1,999 10,393
135 National Business Parkway Annapolis Junction, MD Office 7,923 2,482 9,742
141 National Business Parkway Annapolis Junction, MD Office 7,764 2,396 9,583
710 Route 46 Fairfield, NJ Office 5,864 2,152 8,610
870 - 880 Elkridge Landing Road Linthicum, MD Office 8,613 2,298 9,191
1615 and 1629 Thames Street Baltimore, MD Office 5,767 2,079 8,316
134 National Business Parkway Annapolis Junction, MD Office 7,896 3,684 7,528
920 Elkridge Landing Road Linthicum, MD Office 8,230 2,200 8,778
1302 Concourse Drive Linthicum, MD Office 7,567 2,077 8,307
2605 Interstate Drive Harrisburg, PA Office 4,419 2,089 8,355
900 Elkridge Landing Road Linthicum, MD Office 7,289 1,992 7,967
131 National Business Parkway Annapolis Junction, MD Office 6,172 1,904 7,617
2601 Market Place Harrisburg, PA Office 4,079 1,928 7,713
68 Culver Road Dayton, NJ Office 8,315 861 8,793
999 Corporate Boulevard Linthicum, MD Office 7,862 1,187 8,333
7067 Columbia Gateway Drive Columbia, MD Office 6,054 1,829 7,364
6700 Alexander Bell Drive Columbia, MD Office 5,748 1,755 7,019
7467 Ridge Road Hanover, MD Office 5,982 1,628 6,511
1199 Winterson Road Linthicum, MD Office 5,848 1,598 6,392
6740 Alexander Bell Drive Columbia, MD Office 4,769 1,423 5,691
14502 Greenview Drive Laurel, MD Office 4,780 1,481 5,894
7240 Parkway Drive Hanover, MD Office 3,721 1,495 5,980
849 International Drive Linthicum, MD Office 4,959 1,355 5,422
14504 Greenview Drive Laurel, MD Office 4,628 1,428 5,712
1099 Winterson Road Linthicum, MD Office 4,840 1,322 5,290
1190 Winterson Road Linthicum, MD Office 4,884 1,334 5,337
6716 Alexander Bell Drive Columbia, MD Office 4,161 1,241 4,965
9140 Route 108 Columbia, MD Office 6,500 1,637 5,520
911 Elkridge Landing Road Linthicum, MD Office 4,445 1,215 4,858
6345 Flank Drive Harrisburg, PA Office 4,431 1,323 5,264
104 Interchange Plaza Cranbury, NJ Office 4,610 1,327 5,309
8815 Centre Park Drive Columbia, MD Office 4,053 1,251 5,003
1201 Winterson Road Linthicum, MD Office 4,713 1,288 5,151
2711 Technology Drive Annapolis Junction, MD Office (4) 3,055 3,362
4301 Route 1 Monmouth Junction, NJ Office 3,674 1,210 4,839
6340 Flank Drive Harrisburg, PA Office 4,266 1,273 5,067
101 Interchange Plaza Cranbury, NJ Office 4,043 1,158 4,661
891 Elkridge Landing Road Linthicum, MD Office 4,488 1,233 4,926
2701 Technology Drive Annapolis Junction, MD Office (4) 3,084 3,070
938 Elkridge Landing Road Linthicum, MD Office 4,476 1,195 4,775
901 Elkridge Landing Road Linthicum, MD Office 4,169 1,148 4,574
<Caption>
COSTS CAPITALIZED GROSS AMOUNTS
SUBSEQUENT TO CARRIED AT CLOSE ACCUMULATED YEAR BUILT DEPRECIATION
PROPERTY ACQUISITION OF PERIOD DEPRECIATION OR RENOVATED DATE ACQUIRED LIFE
- ------------------------------------ ------------------ ------------------- ------------ ------------- ------------- --------------
751, 753 760, 785 Jolly Road 99 111,358 (9,321) 1966/1996 10/14/1997 40 Years
15000 Conference Center Drive - 58,968 (111) 1989 11/30/2001 40 Years
2730 Hercules Road 1 39,487 (2,566) 1990 9/28/1998 40 Years
695 Route 46 3,234 21,893 (1,969) 1990 5/28/1998 40 Years
431 Ridge Road 6,936 20,846 (1,893) 1958/1998 10/14/1997 40 Years
7200 Riverwood Drive 35 20,462 (1,308) 1986 10/13/1998 40 Years
6009 - 6011 Oxon Hill Road 1,094 18,254 (1,487) 1990 9/28/1998 40 Years
6731 Columbia Gtwy Drive - 18,234 - (1) 3/29/2000 N/A
9690 Deereco Road 901 18,032 (850) 1988 12/21/1999 40 Years
6950 Columbia Gateway Drive 29 17,880 (1,133) 1998 10/21/1998 40 Years
2721 Technology Drive 1 17,563 (397) 2000 10/21/1999 40 Years
132 National Business Parkway 19 15,362 (514) 2000 5/28/1999 40 Years
429 Ridge Road 356 15,005 (1,283) 1966/1996 10/14/1997 40 Years
1306 Concourse Drive 402 14,373 (643) 1990 11/18/1999 40 Years
6940 Columbia Gateway Drive 107 13,563 (570) 1999 11/13/1998 40 Years
6750 Alexander Bell Drive 5 13,555 (289) 2000 12/31/1998 40 Years
375 W. Padonia Road 48 13,049 (521) 1986 12/21/1999 40 Years
133 National Business Parkway 234 12,809 (941) 1997 9/28/1998 40 Years
1304 Concourse Drive - 12,392 - (1) 11/18/1999 N/A
135 National Business Parkway 66 12,290 (760) 1998 12/30/1998 40 Years
141 National Business Parkway 236 12,215 (830) 1990 9/28/1998 40 Years
710 Route 46 1,021 11,783 (904) 1985 5/28/1998 40 Years
870 - 880 Elkridge Landing Road 42 11,531 (96) 1981 8/3/2001 40 Years
1615 and 1629 Thames Street 1,041 11,436 (850) 1989 9/28/1998 40 Years
134 National Business Parkway 11 11,223 (490) 1999 11/13/1998 40 Years
920 Elkridge Landing Road 74 11,052 (109) 1982 7/2/2001 40 Years
1302 Concourse Drive 471 10,855 (572) 1996 11/18/1999 40 Years
2605 Interstate Drive 222 10,666 (939) 1990 10/14/1997 40 Years
900 Elkridge Landing Road 402 10,361 (844) 1982 4/30/1998 40 Years
131 National Business Parkway 525 10,046 (756) 1990 9/28/1998 40 Years
2601 Market Place 282 9,923 (845) 1989 10/14/1997 40 Years
68 Culver Road 4 9,658 (289) 2000 7/9/1999 40 Years
999 Corporate Boulevard 4 9,524 (325) 2000 8/1/1999 40 Years
7067 Columbia Gateway Drive - 9,193 (61) 2001 8/30/2001 40 Years
6700 Alexander Bell Drive 211 8,985 (114) 1988 5/14/2001 40 Years
7467 Ridge Road 384 8,523 (600) 1990 4/28/1999 40 Years
1199 Winterson Road 154 8,144 (601) 1988 4/30/1998 40 Years
6740 Alexander Bell Drive 830 7,944 (646) 1992 12/31/1998 40 Years
14502 Greenview Drive 465 7,840 (624) 1988 9/28/1998 40 Years
7240 Parkway Drive 345 7,820 (271) 1985 4/18/2000 40 Years
849 International Drive 668 7,445 (496) 1988 2/23/1999 40 Years
14504 Greenview Drive 264 7,404 (550) 1985 9/28/1998 40 Years
1099 Winterson Road 712 7,324 (615) 1988 4/30/1998 40 Years
1190 Winterson Road 642 7,313 (573) 1987 4/30/1998 40 Years
6716 Alexander Bell Drive 988 7,194 (554) 1990 12/31/1998 40 Years
9140 Route 108 34 7,191 (139) 1974/1985 12/14/2000 40 Years
911 Elkridge Landing Road 817 6,890 (628) 1985 4/30/98 40 Years
6345 Flank Drive 134 6,721 (330) 1989 12/3/1999 40 Years
104 Interchange Plaza 41 6,677 (423) 1990 10/30/1998 40 Years
8815 Centre Park Drive 252 6,506 (506) 1987 9/28/1998 40 Years
1201 Winterson Road 21 6,460 (475) 1985 4/30/1998 40 Years
2711 Technology Drive - 6,417 - (1) 11/13/2000 N/A
4301 Route 1 363 6,412 (516) 1986 6/24/1999 40 Years
6340 Flank Drive 50 6,390 (266) 1988 12/3/1999 40 Years
101 Interchange Plaza 533 6,352 (498) 1985 10/30/1998 40 Years
891 Elkridge Landing Road 90 6,249 (62) 1984 7/2/2001 40 Years
2701 Technology Drive - 6,154 (83) 2001 5/26/2000 40 Years
938 Elkridge Landing Road 31 6,001 (60) 1984 7/2/2001 40 Years
901 Elkridge Landing Road 252 5,974 (65) 1984 7/2/2001 40 Years
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<Caption>
INITIAL COST
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BUILDING AND LAND
PROPERTY LOCATION BUILDING TYPE ENCUMBRANCES LAND IMPROVEMENTS
- ------------------------------- ----------------------- -------------------- ------------------- ------------- -----------------
6711 Columbia Gateway Drive Columbia, MD Office - 3,970 1,729
5035 Ritter Road Harrisburg, PA Office 3,736 1,115 4,438
6400 Flank Drive Harrisburg, PA Office 3,659 1,092 4,347
881 Elkridge Landing Road Linthicum, MD Office 3,783 1,034 4,135
7065 Columbia Gateway Drive Columbia, MD Office 3,561 1,081 4,326
939 Elkridge Landing Road Linthicum, MD Office 3,434 938 3,754
921 Elkridge Landing Road Linthicum, MD Office 3,818 1,043 4,174
900 International Drive Linthicum, MD Office 3,705 1,013 4,051
7063 Columbia Gateway Drive Columbia, MD Office 3,411 1,036 4,144
930 International Drive Linthicum, MD Office 3,586 980 3,920
7321 Parkway Drive Hanover, MD Office 3,452 939 3,757
7318 Parkway Drive Hanover, MD Office 3,569 971 3,885
940 Elkridge Landing Road Linthicum, MD Office 3,681 986 3,924
6360 Flank Drive Harrisburg, PA Office 3,049 910 3,622
6760 Alexander Bell Drive Columbia, MD Office 2,982 889 3,558
1340 Ashton Road Hanover, MD Office 3,323 904 3,617
6708 Alexander Bell Drive Columbia, MD Office 2,938 897 3,588
7061 Columbia Gateway Drive Columbia, MD Office 2,725 827 3,310
6385 Flank Drive Harrisburg, PA Office 1,715 811 3,242
800 International Drive Linthicum, MD Office 2,834 774 3,097
1334 Ashton Road Hanover, MD Office 2,704 736 2,943
47 Commerce Cranbury, NJ Office 2,624 756 3,022
437 Ridge Road Dayton, NJ Office 3,086 717 2,866
6724 Alexander Bell Drive Columbia, MD Office 2,313 449 3,082
6405 Flank Drive Harrisburg, PA Office 2,195 655 2,608
5070 Ritter Road- Bldg A Harrisburg, PA Office 1,952 583 2,318
6380 Flank Drive Harrisburg, PA Office 1,973 589 2,344
1331 Ashton Road Hanover, MD Office 2,154 586 2,345
5070 Ritter Road- Bldg B Harrisburg, PA Office 1,708 510 2,028
7 Centre Drive Cranbury, NJ Office 1,631 470 1,879
2 Centre Drive Cranbury, NJ Office 1,667 480 1,919
114 National Business Parkway Annapolis Junction, MD Retail - 364 2,030
95 Shannon Road Harrisburg, PA Office 1,000 472 1,891
75 Shannon Road Harrisburg, PA Office 951 450 1,799
8 Centre Drive Cranbury, NJ Office 1,348 388 1,552
1350 Dorsey Road Hanover, MD Office 1,444 393 1,571
1344 Ashton Road Hanover, MD Office 1,304 355 1,420
6375 Flank Drive Harrisburg, PA Office 715 191 1,499
1341 Ashton Road Hanover, MD Office 1,123 306 1,222
85 Shannon Road Harrisburg, PA Office 586 277 1,109
102 Interchange Cranbury, NJ Office - 641 467
1343 Ashton Road Hanover, MD Office 710 193 773
Commerce 2 Building Harrisburg, PA Office - - 768
1337 Ashton Road Hanover, MD Office - 400 283
Airport Square XXII Linthicum, MD Office - 630 7
6013&6007 Oxon Hill Road Laurel, MD Office - 457 12
1338 Ashton Road Hanover, MD Office 37 50 -
220 National Business Parkway Annapolis Junction, MD Office - - 23
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$571,800 $191,650 $746,043
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<Caption>
COSTS CAPITALIZED GROSS AMOUNTS
SUBSEQUENT TO CARRIED AT CLOSE ACCUMULATED YEAR BUILT DEPRECIATION
PROPERTY ACQUISITION OF PERIOD DEPRECIATION OR RENOVATED DATE ACQUIRED LIFE
- ------------------------------------ ------------------ ------------------- ------------ ------------- ------------- --------------
6711 Columbia Gateway Drive - 5,699 - (1) 9/28/2000 N/A
5035 Ritter Road 16 5,569 (233) 1988 12/3/1999 40 Years
6400 Flank Drive 25 5,464 (228) 1992 12/3/1999 40 Years
881 Elkridge Landing Road 249 5,418 (394) 1986 4/30/1998 40 Years
7065 Columbia Gateway Drive - 5,407 (36) 2000 8/30/2001 40 Years
939 Elkridge Landing Road 623 5,315 (405) 1983 4/30/1998 40 Years
921 Elkridge Landing Road 60 5,277 (385) 1983 4/30/1998 40 Years
900 International Drive 185 5,249 (382) 1986 4/30/1998 40 Years
7063 Columbia Gateway Drive - 5,180 (34) 2000 8/30/2001 40 Years
930 International Drive 211 5,111 (366) 1986 4/30/1998 40 Years
7321 Parkway Drive 355 5,051 (335) 1984 4/16/1999 40 Years
7318 Parkway Drive 91 4,947 (273) 1984 4/16/1999 40 Years
940 Elkridge Landing Road 29 4,939 (49) 1984 7/2/2001 40 Years
6360 Flank Drive 199 4,731 (223) 1988 12/3/1999 40 Years
6760 Alexander Bell Drive 228 4,675 (277) 1991 12/31/1998 40 Years
1340 Ashton Road 1 4,522 (241) 1989 4/28/1999 40 Years
6708 Alexander Bell Drive 2 4,487 (52) 1988 5/14/2001 40 Years
7061 Columbia Gateway Drive - 4,137 (28) 2000 8/30/2001 40 Years
6385 Flank Drive 10 4,063 (347) 1995 10/14/1997 40 Years
800 International Drive 74 3,945 (302) 1988 4/30/1998 40 Years
1334 Ashton Road 101 3,780 (228) 1989 4/28/1999 40 Years
47 Commerce 1 3,779 (239) 1992/1998 10/30/1998 40 Years
437 Ridge Road 28 3,611 (307) 1962/1996 10/14/1997 40 Years
6724 Alexander Bell Drive - 3,531 - (1) 5/14/2001 N/A
6405 Flank Drive 6 3,269 (136) 1991 12/3/1999 40 Years
5070 Ritter Road- Bldg A 211 3,112 (187) 1989 12/3/1999 40 Years
6380 Flank Drive 58 2,991 (127) 1991 12/3/1999 40 Years
1331 Ashton Road - 2,931 (156) 1989 4/28/1999 40 Years
5070 Ritter Road- Bldg B 43 2,581 (115) 1989 12/3/1999 40 Years
7 Centre Drive 87 2,436 (200) 1989 10/30/1998 40 Years
2 Centre Drive - 2,399 (151) 1989 10/30/1998 40 Years
114 National Business Parkway - 2,394 - (1) 6/30/2000 N/A
95 Shannon Road 3 2,366 (114) 1995 8/12/1999 40 Years
75 Shannon Road 107 2,356 (124) 1995 8/12/1999 40 Years
8 Centre Drive 256 2,196 (229) 1986 10/30/1998 40 Years
1350 Dorsey Road 200 2,164 (123) 1989 4/28/1999 40 Years
1344 Ashton Road 90 1,865 (98) 1989 4/28/1999 40 Years
6375 Flank Drive 37 1,727 (41) 2000 11/4/1999 40 Years
1341 Ashton Road 79 1,607 (107) 1989 4/28/1999 40 Years
85 Shannon Road 3 1,389 (67) 1995 8/12/1999 40 Years
102 Interchange - 1,108 - (1) (3) N/A
1343 Ashton Road 1 967 (52) 1989 4/28/1999 40 Years
Commerce 2 Building - 768 - (1) (3) N/A
1337 Ashton Road - 683 - (2) 4/28/1999 N/A
Airport Square XXII - 637 - (2) 12/19/2001 N/A
6013&6007 Oxon Hill Road - 469 - (2) 7/30/2001 N/A
1338 Ashton Road 12 62 - (2) 4/28/1999 N/A
220 National Business Parkway - 23 - (1) (3) N/A
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$29,863 $967,558 $(51,552)
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(1) Under construction or development at December 31, 2001.
(2) Held for future development at December 31, 2001.
(3) Development in progress in anticipation of acquisition
(4) Encumbrances for property resides in joint venture.
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The following table summarizes our changes in cost of properties (in thousands):
<Table>
Balance at December 31, 2000 $ 781,242
Property acquisitions 144,780
Building and land improvements 49,809
Sales (8,273)
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Balance at December 31, 2001 $ 967,558
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The following table summarizes our changes in accumulated depreciation (in
thousands):
<Table>
Balance at December 31, 2000 $ 33,271
Depreciation expense 18,697
Sales (416)
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Balance at December 31, 2001 $ 51,552
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