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Exhibit 12.1

AVALONBAY COMMUNITIES, INC.
RATIOS OF EARNINGS TO COMBINED FIXED CHARGES AND
PREFERRED STOCK DIVIDENDS

|  | Year Ended December 31, 2012(1) |  | Year Ended December 31, 2011(1) |  | Year Ended December 31, 2010(1) |  | Year Ended December 31, 2009(1) |  | Year Ended December 31, 2008(1) |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Income from continuing operations before cumulative effect of change in accounting principle |  | $ | 264,756 |  | $ | 152,400 |  | $ | 92,055 |  | $ | 70,011 |  | $ | 90,913 |
(Plus): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in income of unconsolidated entities, net of distributions received |  |  | 11,170 |  |  | 618 |  |  | 4,856 |  |  | 5,475 |  |  | 6,728 |
Amortization of capitalized interest(2) |  |  | 17,929 |  |  | 16,277 |  |  | 15,149 |  |  | 14,035 |  |  | 12,428 |
Earnings before fixed charges |  | $ | 293,855 |  | $ | 169,295 |  | $ | 112,060 |  | $ | 89,521 |  | $ | 110,069 |
(Plus) Fixed charges: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Portion of rents representative of the interest factor |  | $ | 6,873 |  | $ | 6,933 |  | $ | 11,785 |  | $ | 6,241 |  | $ | 5,287 |
Interest expense |  |  | 136,920 |  |  | 167,814 |  |  | 169,997 |  |  | 145,090 |  |  | 110,250 |
Interest capitalized |  |  | 49,556 |  |  | 33,863 |  |  | 33,393 |  |  | 48,226 |  |  | 74,621 |
Preferred dividend |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 10,454 |
Total fixed charges(3) |  | $ | 193,349 |  | $ | 208,610 |  | $ | 215,175 |  | $ | 199,557 |  | $ | 200,612 |
(Less): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest capitalized |  |  | 49,556 |  |  | 33,863 |  |  | 33,393 |  |  | 48,226 |  |  | 74,621 |
Preferred dividend |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 10,454 |
Earnings(4) |  | $ | 437,648 |  | $ | 344,042 |  | $ | 293,842 |  | $ | 240,852 |  | $ | 225,606 |
Ratio (4 divided by 3) |  |  | 2.26 |  |  | 1.65 |  |  | 1.37 |  |  | 1.21 |  |  | 1.12 |

AVALONBAY COMMUNITIES, INC.
RATIOS OF EARNINGS TO FIXED CHARGES

|  | Year Ended December 31, 2012(1) |  | Year Ended December 31, 2011(1) |  | Year Ended December 31, 2010(1) |  | Year Ended December 31, 2009(1) |  | Year Ended December 31, 2008(1) |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Income from continuing operations before cumulative effect of change in accounting principle |  | $ | 264,756 |  | $ | 152,400 |  | $ | 92,055 |  | $ | 70,011 |  | $ | 90,913 |
(Plus): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity in income of unconsolidated entities, net of distributions received |  |  | 11,170 |  |  | 618 |  |  | 4,856 |  |  | 5,475 |  |  | 6,728 |
Amortization of capitalized interest(2) |  |  | 17,929 |  |  | 16,277 |  |  | 15,149 |  |  | 14,035 |  |  | 12,428 |
Earnings before fixed charges |  | $ | 293,885 |  | $ | 169,295 |  | $ | 112,060 |  | $ | 89,521 |  | $ | 110,069 |
(Plus) Fixed charges: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Portion of rents representative of the interest factor |  | $ | 6,873 |  | $ | 6,933 |  | $ | 11,785 |  | $ | 6,241 |  | $ | 5,287 |
Interest expense |  |  | 136,920 |  |  | 167,814 |  |  | 169,997 |  |  | 145,090 |  |  | 110,250 |
Interest capitalized |  |  | 49,556 |  |  | 33,863 |  |  | 33,393 |  |  | 48,226 |  |  | 74,621 |
Total fixed charges(3) |  | $ | 193,349 |  | $ | 208,610 |  | $ | 215,175 |  | $ | 199,557 |  | $ | 190,158 |
(Less): |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest capitalized |  |  | 49,556 |  |  | 33,863 |  |  | 33,393 |  |  | 48,226 |  |  | 74,621 |
Earnings(4) |  | $ | 437,648 |  | $ | 344,042 |  | $ | 293,842 |  | $ | 240,852 |  | $ | 225,606 |
Ratio (4 divided by 3) |  |  | 2.26 |  |  | 1.65 |  |  | 1.37 |  |  | 1.21 |  |  | 1.19 |

(1)
  The results of operations for 2008 through 2012 have been adjusted to reflect discontinued operations for properties sold or held for sale as of December 31, 2012.
(2)
  Represents an estimate of capitalized interest costs based on the Company's established depreciation policy and an analysis of interest costs capitalized since 1998 (the year in which AvalonBay was formed).

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Exhibit 12.1

AVALONBAY COMMUNITIES, INC. RATIOS OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS
AVALONBAY COMMUNITIES, INC. RATIOS OF EARNINGS TO FIXED CHARGES