Income Taxes

Income Tax Expense. Our income tax expense and effective income tax rate were as follows (dollars in thousands):



	Three Months Ended
	February 28, 2017			February 29, 2016
Income tax expense (a)	$	7,200		$	2,900
Effective income tax rate (a)	33.6		%	18.1		%


(a)	Amounts reflect the favorable net impact of federal energy tax credits we earned from building energy-efficient homes. The net impact of these tax credits was $1.1 million and $3.3 million for the three months ended February 28, 2017 and February 29, 2016, respectively.

The majority of the federal energy tax credits for the three-month periods ended February 28, 2017 and February 29, 2016 resulted from legislation enacted in 2015 that extended the availability of a business tax credit for building new energy-efficient homes through December 31, 2016. There has been no new legislation enacted extending the business tax credit beyond December 31, 2016.

Deferred Tax Asset Valuation Allowance. We evaluate our deferred tax assets quarterly to determine if adjustments to our valuation allowance are required based on the consideration of all available positive and negative evidence using a “more likely than not” standard with respect to whether deferred tax assets will be realized. Our evaluation considers, among other factors, our historical operating results, our expectation of future profitability, the duration of the applicable statutory carryforward periods, and conditions in the housing market and the broader economy. The ultimate realization of our deferred tax assets depends primarily on our ability to generate future taxable income during the periods in which the related temporary differences in the financial basis and the tax basis of the assets become deductible. The value of our deferred tax assets depends on applicable income tax rates.

Our deferred tax assets of $756.7 million as of February 28, 2017 and $763.8 million as of November 30, 2016 were partly offset by a valuation allowance in each period of $24.8 million. The deferred tax asset valuation allowances as of February 28, 2017 and November 30, 2016 were primarily related to certain state net operating losses (“NOLs”) that had not met the “more likely than not” realization standard at those dates. Based on our evaluation of our deferred tax assets as of February 28, 2017, we determined that most of our deferred tax assets would be realized. Therefore, we made no adjustments to our deferred tax valuation allowance during the three months ended February 28, 2017.

We will continue to evaluate both the positive and negative evidence on a quarterly basis in determining the need for a valuation allowance with respect to our deferred tax assets. The accounting for deferred tax assets is based upon estimates of future results. Changes in positive and negative evidence, including differences between estimated and actual results, could result in changes in the valuation of our deferred tax assets that could have a material impact on our consolidated financial statements. Changes in existing federal and state tax laws and corporate income tax rates could also affect actual tax results and the realization of deferred tax assets over time.

Unrecognized Tax Benefits. At both February 28, 2017 and November 30, 2016, our gross unrecognized tax benefits (including interest and penalties) totaled $.1 million, all of which, if recognized, would affect our effective income tax rate. We anticipate that these gross unrecognized tax benefits will decrease by an amount ranging from zero to $.1 million during the 12 months from this reporting date. The fiscal years ending 2013 and later remain open to federal examinations, while fiscal years 2012 and later remain open to state examinations.