Investment in Oil and Gas Properties

The following tables disclose certain financial data relative to the Company’s oil and gas producing activities, which are located onshore and offshore in the continental United States:

Costs Incurred in Oil and Gas Property Acquisition, Exploration and Development Activities

(amounts in thousands)



	For the Year-Ended December 31,
	2012			2011			2010
Acquisition costs:
Proved	$	352		$	2,720		$	10,421
Unproved	15,677			43,207			11,310
Divestitures—unproved (1)	(8,889		)	(14,461		)	(36,139		)
Exploration costs:
Proved	72,361			92,466			34,310
Unproved	18,033			5,919			10,384
Development costs	18,740			34,400			34,286
Capitalized general and administrative and interest costs	18,961			18,210			19,665
Total costs incurred	$	135,235		$	182,461		$	84,237



	For the Year-Ended December 31,
	2012			2011			2010
Accumulated depreciation, depletion and amortization (DD&A)
Balance, beginning of year	$	(1,265,603	)	$	(1,175,553	)	$	(1,082,381	)
Provision for DD&A	(59,496		)	(57,143		)	(58,172		)
Ceiling test writedown	(137,100		)	(18,907		)	—
Sale of proved properties and other (2)	(10,045		)	(14,000		)	(35,000		)
Balance, end of year	$	(1,472,244	)	$	(1,265,603	)	$	(1,175,553	)

DD&A per Mcfe	$	1.75		$	1.89		$	1.88


(1)	During 2012, the Company sold an additional portion of its Mississippian Lime acreage for $6.1 million. During 2011, the Company sold a portion of its unproved Mississippian Lime acreage for $14.5 million. During 2010, the Company recorded $36 million in consideration from the sale of a portion of its unevaluated acreage in the Woodford as part of its Woodford joint development agreement.

(2)

During 2012, the Company sold its non-operated Arkansas assets for a net cash purchase price of $9.2 million. During 2011, the Company received an additional $14 million payment associated with the achievement of certain production metrics stipulated under the joint development agreement (See Note 3). During 2010, the Company recorded $35 million in consideration from the sale of a portion of its evaluated properties in the Woodford as part of its Woodford joint development agreement.

At December 31, 2012 and 2011, unevaluated oil and gas properties totaled $71.7 million and $70.4 million, respectively, and were not subject to depletion. Unevaluated costs at December 31, 2012 included $12.7 million of costs related to 17 exploratory wells in progress at year-end. These costs are expected to be transferred to evaluated oil and gas properties during 2013 upon the completion of drilling. At December 31, 2011, unevaluated costs included $5.9 million related to 44 exploratory wells in progress. All of these costs were transferred to evaluated oil and gas properties during 2012. The Company capitalized $7.0 million, $7.0 million and $7.8 million of interest during 2012, 2011 and 2010, respectively. Of the total unevaluated oil and gas property costs of $71.7 million at December 31, 2012, $24.8 million, or 35%, was incurred in 2012, $26.5 million, or 37%, was incurred in 2011 and $20.4 million, or 28%, was incurred in prior years. The Company expects that the majority of the unevaluated costs at December 31, 2012 will be evaluated within the next three years, including $28.3 million that the Company expects to be evaluated during 2013.