Petrohawk Energy 8-K Receivables from derivative contracts

Exhibit 99.1

Petrohawk Energy Corporation

Unaudited Pro Forma Consolidated Balance Sheet

(In thousands)

	September 30, 2009
	Historical			Adjustments			Pro Forma
Current assets:
Cash	$	1,692		$	—		$	1,692
Marketable securities		150,028			—			150,028
Accounts receivable		181,915			—			181,915
Receivables from derivative contracts		150,346			—			150,346
Prepaids and other		42,079			—			42,079
Total current assets		526,060			—			526,060
Oil and natural gas properties(full cost method):
Evaluated		5,947,489			(383,822	)(1)		5,563,667
Unevaluated		2,332,134			(1,748	)(2)		2,330,386
Gross oil and natural gas properties		8,279,623			(385,570	)		7,894,053
Less—accumulated depletion		(4,122,596	)		—			(4,122,596	)
Net oil and natural gas properties		4,157,027			(385,570	)		3,771,457
Other operating property and equipment:
Gas gathering system and equipment		448,596			—			448,596
Other operating assets		24,301			—			24,301
Gross other operating property and equipment		472,897			—			472,897
Less—accumulated depreciation		(21,347	)		—			(21,347	)
Net other operating property and equipment		451,550			—			451,550
Other noncurrent assets:
Goodwill		932,802			—			932,802
Other intangible assets		103,266			—			103,266
Deferred income taxes		173,037			—			173,037
Debt issuance costs, net of amortization		36,586			—			36,586
Receivables from derivative contracts		24,589			—			24,589
Restricted cash		—			338,400	(3)		338,400
Other		2,551						2,551
Total assets	$	6,407,468		$	(47,170	)	$	6,360,298
Current liabilities:
Accounts payable and accrued liabilities	$	610,496		$	(37,600	)(1)	$	572,896
Deferred income taxes		42,976			—			42,976
Liabilities from derivative contracts		363			—			363
Long-term debt		39,821			—			39,821
Total current liabilities		693,656			(37,600	)		656,056
Long-term debt		2,394,270			—			2,394,270
Other noncurrent liabilities:
Liabilities from derivative contracts		1,237			—			1,237
Asset retirement obligations		31,660			(9,570	)(4)		22,090
Other		4,235			—			4,235
Commitments and contingencies
Stockholders' equity:
Common stock		301			—			301
Additional paid-in capital		4,594,885			—			4,594,885
Accumulated deficit		(1,312,776	)		—			(1,312,776	)
Total stockholders’ equity		3,282,410			—			3,282,410
Total liabilities and stockholders’ equity	$	6,407,468		$	(47,170	)	$	6,360,298

See accompanying notes to the unaudited pro forma consolidated financial statements.

Petrohawk Energy Corporation

Unaudited Pro Forma Consolidated Statement of Operations

(In thousands, except per share amounts)

	Nine Months Ended September 30, 2009
	Petrohawk Historical			Adjustments			Petrohawk Pro Forma
Operating revenues:
Oil and natural gas	$	512,528		$	(46,392	)(5)	$	466,136
Marketing		216,165			—			216,165
Total operating revenues		728,693			(46,392	)		682,301
Operating expenses:
Marketing		211,722			—			211,722
Production:
Lease operating		55,903			(12,348	)(5)		43,555
Workover and other		1,793			(501	)(5)		1,292
Taxes other than income		39,921			(2,782	)(5)		37,139
Gathering, transportation and other		65,870			(1,114	)(5)		64,756
General and administrative		68,181			—			68,181
Depletion, depreciation and amortization		290,383			(26,930	)(6)		263,106
					(347	)(4)
Full cost ceiling impairment		1,732,486			(180,580	)(7)		1,551,906
Total operating expenses		2,466,259			(224,602	)		2,241,657
(Loss) income from operations		(1,737,566	)		178,210			(1,559,356	)
Other income:
Net gain on derivative contracts		196,360			—			196,360
Interest expense and other		(170,929	)		—			(170,929	)
Total other income		25,431			—			25,431
(Loss) income before income taxes		(1,712,135	)		178,210			(1,533,925	)
Income tax benefit (provision)		650,201			(67,677	)(8)		582,524
Net (loss) income available to common stockholders	$	(1,061,934	)	$	110,533		$	(951,401	)
Net loss per share of common stock:
Basic	$	(3.88	)				$	(3.48	)
Diluted	$	(3.88	)				$	(3.48	)
Weighted average shares outstanding:
Basic		273,477						273,477
Diluted		273,477						273,477

See accompanying notes to the unaudited pro forma consolidated financial statements.

Petrohawk Energy Corporation

Unaudited Pro Forma Consolidated Statement of Operations

(In thousands, except per share amounts)

	Year Ended December 31, 2008
	Petrohawk Historical			Adjustments			Petrohawk Pro Forma
Operating revenues:
Oil and natural gas	$	1,031,657		$	(140,313	)(5)	$	891,344
Marketing		63,553			—			63,553
Total operating revenues		1,095,210			(140,313	)		954,897
Operating expenses:
Marketing		58,581			—			58,581
Production:
Lease operating		52,477			(18,687	)(5)		33,790
Workover and other		5,624			(2,897	)(5)		2,727
Taxes other than income		47,104			(12,091	)(5)		35,013
Gathering, transportation and other		47,309			(1,783	)(5)		45,526
General and administrative		74,810			—			74,810
Depletion, depreciation and amortization		396,556			(8,248	)(6)		387,872
					(436	)(4)
Full cost ceiling impairment		950,799			(104,947	)(7)		845,852
Total operating expenses		1,633,260			(149,089	)		1,484,171
(Loss) income from operations		(538,050	)		8,776			(529,274	)
Other income:
Net gain on derivative contracts		156,870			—			156,870
Interest expense and other		(151,825	)		—			(151,825	)
Total other income		5,045			—			5,045
(Loss) income before income taxes		(533,005	)		8,776			(524,229	)
Income tax benefit (provision)		144,953			(2,387	)(8)		142,566
Net (loss) income available to common stockholders	$	(388,052	)	$	6,389		$	(381,663	)
Net loss per share of common stock:
Basic	$	(1.77	)				$	(1.74	)
Diluted	$	(1.77	)				$	(1.74	)
Weighted average shares outstanding:
Basic		218,993						218,993
Diluted		218,993						218,993

See accompanying notes to the unaudited pro forma consolidated financial statements.

Petrohawk Energy Corporation

Notes to Unaudited Pro Forma Consolidated Financial Statements

Note 1 – Basis of Presentation

The unaudited pro forma financial information is presented to illustrate the effect of Petrohawk’s October 30, 2009 sale of its Permian Basin properties on its historical financial position and operating results. The unaudited pro forma balance sheet as of September 30, 2009 is based on the historical statements of Petrohawk as of September 30, 2009 after giving effect to the transaction as if it had occurred on September 30, 2009. The unaudited pro forma statements of operations for the nine months ended September 30, 2009 and the fiscal year ended December 31, 2008 are based on the historical financial statements of Petrohawk for such periods after giving effect to the transaction as if it had occurred on January 1, 2008. The unaudited pro forma financial information should be read in conjunction with Petrohawk’s historical consolidated financial statements and notes thereto contained in Petrohawk’s 2008 Annual Report on Form 10-K, as amended, filed on April 30, 2009, and Petrohawk’s Form 10-Q for the quarter ended September 30, 2009, filed on November 4, 2009.

The preparation of the unaudited pro forma consolidated financial information is based on financial statements prepared in accordance with accounting principles generally accepted in the United States of America. These principles require the use of estimates that affect the reported amounts of assets, liabilities, revenues and expenses. Actual results could differ from those estimates.

The unaudited pro forma consolidated financial information is provided for illustrative purposes only and does not purport to represent what the actual results of operations or the financial position of the company would have been had the transactions occurred on the respective dates assumed, nor is it necessarily indicative of the Company’s future operating results or financial position. However, the pro forma adjustments reflected in the accompanying unaudited pro forma consolidated financial information reflect estimates and assumptions that the company’s management believes to be reasonable.

Note 2 – Pro Forma Adjustments

The unaudited pro forma consolidated balance sheet at September 30, 2009 reflects the following adjustments:

(1) Adjustment to reduce the full cost pool for the sale of the Company’s Permian Basin assets, $37.6 million had already been received by the Company as of September 30, 2009 as a deposit;

(2) Adjustment to reduce unevaluated oil and natural gas properties associated with the Company’s Permian Basin assets;

(3) Reflects the $338.4 million received directly by a qualified intermediary to facilitate like-kind exchange transactions; and

(4) Reflects the elimination of asset retirement obligations associated with the Permian Basin assets that were sold.

The unaudited pro forma consolidated statements of operations for the year ended December 31, 2008 and for the nine months ended September 30, 2009 reflect the following adjustments:

(5) Reflects the elimination of oil and gas revenues and operating expenses associated with the Permian Basin assets that were sold;

(6) To adjust historical depletion expense associated with oil and natural gas properties as if the sale of the Permian Basin assets had occurred on January 1, 2008. Depletion expense is calculated using the unit of production method under full cost accounting;

(7) Reflects the elimination of a portion of the Company’s full cost ceiling impairments associated with the Permian Basin assets that were sold; and

(8) Adjustment to record income tax expense on the unaudited pro forma consolidated results of operations based on the Company’s historical effective tax rates of 27.2% for the year ended December 31, 2008, and 38.0% for the nine months ended September 30, 2009.

Petrohawk will incur approximately $0.5 million in transaction costs. This amount consists of costs associated with employee severance payments. These costs are directly attributable to the transaction and have been excluded from the pro forma financial statements as they represent material nonrecurring charges.