Exhibit 12.1

RATIO OF EARNINGS TO FIXED CHARGES AND

RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND

PREFERRED UNIT DISTRIBUTIONS

	Three Months Ended March 31, 2007		Year Ended December 31,
			2006		2005		2004		2003		2002
			(dollars in thousands)
Earnings:
Income from continuing operations before minority interest and equity in earnings of unconsolidated affiliates	$	27,187	$	32,091	$	18,020	$	13,046	$	848	$	28,415
Contractual interest expense		22,631		94,193		98,677		104,594		117,653		118,086
Amortization of deferred financing costs		566		2,375		3,372		3,698		4,398		3,647
Financing obligations interest expense		992		4,162		5,032		9,999		17,691		12,488
Distributions of earnings from unconsolidated affiliates		1,898		7,335		8,516		6,410		4,320		5,612
Total earnings	$	53,274	$	140,156	$	133,617	$	137,747	$	144,910	$	168,248
Fixed charges and Preferred Unit distributions
Contractual interest expense	$	22,631	$	94,193	$	98,677	$	104,594	$	117,653	$	118,086
Amortization of deferred financing costs		566		2,375		3,372		3,698		4,398		3,647
Financing obligations interest expense		992		4,162		5,032		9,999		17,691		12,488
Capitalized interest		2,147		5,002		2,900		1,058		1,398		5,461
Interest component of rental expense		361		1,481		1,606		1,789		1,721		1,898
Total fixed charges		26,697		107,213		111,587		121,138		142,861		141,580
Preferred Unit distributions		4,113		17,063		27,238		30,852		30,852		30,852
Total fixed charges and Preferred Unit distributions	$	30,810	$	124,276	$	138,825	$	151,990	$	173,713	$	172,432
Ratio of earnings to fixed charges		2.00		1.31		1.20		1.14		1.01		1.19
Ratio of earnings to combined fixed charges and Preferred Unit distributions		1.73		1.13		0.96		0.91		0.83		0.98