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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