MDU RESOURCES GROUP, INC.

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

AND COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS

	Years Ended December 31,
	2010			2009			2008			2007			2006
	(In thousands of dollars)
Earnings Available for Fixed Charges:
Net Income (a)	$	218,205		$	(126,653	)	$	293,826		$	308,288		$	303,396
Income Taxes		122,530			(96,092	)		147,475			190,024			166,110
		340,735			(222,745	)		441,301			498,312			469,506
Rents (b)		12,897			14,475			11,781			11,947			7,688
Interest (c)		88,930			89,943			86,320			76,248			74,531
Total Earnings Available for Fixed Charges	$	442,562		$	(118,327	)	$	539,402		$	586,507		$	551,725
Preferred Dividend Requirements	$	685		$	685		$	685		$	685		$	685
Ratio of Income Before Income Taxes to Net Income		156	%		176	%		150	%		159	%		154	%
Preferred Dividend Factor on Pretax Basis		1,069			1,206			1,028			1,089			1,055
Fixed Charges (d)		107,552			109,117			101,452			90,545			84,898
Combined Fixed Charges and Preferred Stock Dividends	$	108,621		$	110,323		$	102,480		$	91,634		$	85,953
Ratio of Earnings to Fixed Charges		4.1	x		—	(e)		5.3	x		6.5	x		6.5	x
Ratio of Earnings to Combined Fixed Charges and Preferred Stock Dividends		4.1	x		—	(e)		5.3	x		6.4	x		6.4	x

(a) Net income excludes undistributed income for equity investees.

(b) Represents interest portion of rents estimated at 33 1/3%.

(c) Represents interest, amortization of debt discount and expense on all indebtedness and amortization of interest capitalized, and excludes amortization of gains or losses on reacquired debt (which, under the Federal Energy Regulatory Commission Uniform System of Accounts, is classified as a reduction of, or increase in, interest expense in the Consolidated Statements of Income) and interest capitalized.

(d) Represents rents (as defined above), interest, amortization of debt discount and expense on all indebtedness, and excludes amortization of gains or losses on reacquired debt (which, under the Federal Energy Regulatory Commission Uniform System of Accounts, is classified as a reduction of, or increase in, interest expense in the Consolidated Statements of Income).

(e) Due to the $384.4 million after-tax noncash write-down of natural gas and oil properties in the first quarter of 2009, earnings were insufficient by $228.7 million to cover combined fixed charges and preferred stock dividends for the twelve months ended December 31, 2009. If the $384.4 million after-tax noncash write-down is excluded, the ratio of earnings to fixed charges and the ratio of earnings to combined fixed charges and preferred stock dividends would both have been 4.6 times for the twelve months ended December 31, 2009.

The above ratios related to fixed charges and combined fixed charges and preferred stock dividends that exclude the effect of the after-tax noncash write-down of natural gas and oil properties are non-GAAP financial measures. The Company believes that these non-GAAP financial measures are useful because the write-down excluded is not indicative of the Company’s cash flows available to meet its fixed charges obligations. The presentation of this additional information is not meant to be considered a substitute for financial measures prepared in accordance with GAAP.