Boston Properties (BXP) 10-K 2006 FY Annual report

EXHIBIT 12.1

BOSTON PROPERTIES, INC.

CALCULATION OF RATIOS OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERRED DISTRIBUTIONS

Boston Properties, Inc.'s ratios of earnings to combined fixed charges and preferred distributions for the five years ended December 31, 2006 were as follows:

	Year Ended December 31,
	2006			2005			2004			2003			2002
	(dollars in thousands)
Earnings:
Add:
Income before minority interests in property partnerships, income from unconsolidated joint ventures, minority interest in Operating Partnership, gains on sales of real estate and other assets, discontinued operations, cumulative effect of a change in accounting principle and preferred dividend	$	313,697		$	304,324		$	304,864		$	288,475		$	263,625
Gains on sales of real estate and other assets		719,826			182,542			9,822			70,244			232,304
Amortization of interest capitalized		3,387			3,298			2,845			2,640			2,526
Distributions from unconsolidated joint ventures		8,206			7,179			6,663			8,412			8,692
Combined fixed charges and preferred distributions (see below)		326,995			340,589			334,082			342,244			316,835
Subtract:
Interest capitalized		(5,921	)		(5,718	)		(10,849	)		(19,200	)		(22,510	)
Preferred distributions		(22,814	)		(26,780	)		(17,063	)		(23,608	)		(31,258	)
Total earnings	$	1,343,376		$	805,434		$	630,364		$	669,207		$	770,214
Combined fixed charges and preferred distributions:
Interest expensed	$	298,260		$	308,091		$	306,170		$	299,436		$	263,067
Interest capitalized		5,921			5,718			10,849			19,200			22,510
Preferred distributions		22,814			26,780			17,063			23,608			31,258
Total combined fixed charges and preferred distributions	$	326,995		$	340,589		$	334,082		$	342,244		$	316,835
Ratio of earnings to combined fixed charges and preferred distributions		4.11			2.36			1.89			1.96			2.43

The ratio of earnings to combined fixed charges and preferred distributions was computed by dividing earnings by combined fixed charges and preferred distributions. Earnings consist of income before minority interests in property partnerships, income from unconsolidated joint ventures, minority interest in Operating Partnership, discontinued operations, cumulative effect of a change in accounting principle and preferred dividend, plus amortization of interest capitalized, distributions from unconsolidated joint ventures, and combined fixed charges and preferred distributions, minus interest capitalized and preferred distributions. Combined fixed charges and preferred distributions consist of interest expensed, which includes credit enhancement fees and amortization of loan costs, interest capitalized, and preferred distributions.