6.INCOME TAXES

Income tax expense attributable to earnings consisted of the following components:



		Years ended April 30,
		2013		2012		2011
Current tax expense
Federal	$	23,519	$	9,937	$	(6,171)
State		4,455		2,345		1,871
		27,974		12,282		(4,300)
Deferred tax expense		36,530		54,442		60,914
Total income tax provision	$	64,504	$	66,724	$	56,614

The tax effects of temporary differences that gave rise to significant portions of the deferred tax assets and deferred tax liabilities were as follows:



		As of April 30,
		2013		2012		2011
Deferred tax assets
Accrued liabilities	$	9,916	$	13,143	$	10,405
Deferred compensation		6,050		5,663		5,325
Unrecognized tax benefits		3,128		2,638		2,135
State net operating loss		3,902		4,395		2,771
Other		1,016		611		656
Total gross deferred tax assets		24,012		26,450		21,292
Deferred tax liabilities
Excess of tax over book
depreciation		(295,951)		(264,757)		(211,415)
Goodwill		(11,919)		(8,955)		(2,550)
Other		66		-		-
Total gross deferred tax
liabilities		(307,804)		(273,712)		(213,965)
Net deferred tax liability	$	(283,792)	$	(247,262)	$	(192,673)

At April 30, 2013, the Company has net operating loss carryforwards for state income tax purposes of approximately $93,805, which are available to offset future taxable income. These net operating loss carryforwards expire during the years 2016 through 2033.

There was no valuation allowance for deferred tax assets as of April 30, 2013 and 2012. There was no net change in the valuation allowance for the years ended April 30, 2013 and 2012. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected taxable income, and tax planning strategies in making this assessment.

Total reported tax expense applicable to the Company’s continuing operations varies from the tax that would have resulted from applying the statutory U.S. federal income tax rates to income before income taxes.



	Years ended April 30,
	2013	2012	2011
Income taxes at the statutory rates	35.0%	35.0%	35.0%
Federal tax credits	-1.7	-2.1	-1.2
State income taxes, net of federal tax
benefit	2.6	2.9	2.9
Other	0.9	0.6	0.7
	36.8%	36.4%	37.4%

The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount that is greater than 50% likely of being realized. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company had a total of $8,938 and $7,538 in gross unrecognized tax benefits at April 30, 2013 and 2012, respectively. Of this amount, $5,810 represents the amount of unrecognized tax benefits that, if recognized, would impact our effective tax rate. Unrecognized tax benefits increased $1,400 during the twelve months ended April 30, 2013, due primarily to the expiration of certain statute of limitations offset by a greater increase associated with income tax filing positions for the current year. This had the effect of increasing the effective tax rate during the fiscal year ending April 30, 2013.

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:



		2013		2012
Beginning balance	$	7,538	$	6,148
Additions based on tax positions related to current year		2,807		2,706
Additions for tax positions of prior years		-		142
Reductions for tax positions of prior years		(37)		(47)
Reductions due to lapse of applicable statute of limitations		(1,370)		(1,411)
Settlements		-		-
Ending balance	$	8,938	$	7,538

The total net amount of accrued interest and penalties for such unrecognized tax benefits was $286 and $249 at April 30, 2013 and 2012, respectively, and is included in other long-term liabilities. Net interest and penalties included in income tax expense for the twelve month period ended April 30, 2013 was an increase in tax expense of $37 and a increase of $4 for the year ended April 30, 2012. At this time, the Company’s best estimate of the reasonably possible change in the amount of the gross unrecognized tax benefits is a decrease of $1,491 during the next twelve months mainly due to the expiration of certain statute of limitations. The federal statute of limitations remains open for the years 2010 and forward. Tax years 2009 and forward are subject to audit by state tax authorities depending on open statute of limitations waivers and the tax code of each state.