The following is a reconciliation of the provision for income taxes computed at the federal statutory rate to income taxes computed at the effective rate:



	For the three months ended				For the nine months ended
	September 30,				September 30,

	2019		2018		2019		2018

Consolidated tax provision at federal statutory rate	21.0	%	21.0	%	21.0	%	21.0	%
State income tax provisions, net of federal income
tax benefit	(0.7)		0.8		1.3		0.4
Remeasurement of certain deferred tax balances	-		-		-		0.9
Tax reserve adjustment	(0.1)		0.5		-		0.5
Changes in certain deferred tax balances	(0.6)		(10.4)		(1.8)		(8.6)
Goodwill impairment	(15.9)		(10.4)		(10.7)		(10.3)
Loss on disposal of Northwest Operations	1.8		-		(1.2)		-
Shared-based payments	-		-		(0.1)		(0.8)
Federal research and development tax credit	0.3		(1.0)		-		(1.0)
All other, net	(0.2)		0.4		-		0.4
Effective tax rate	5.6	%	0.9	%	8.5	%	2.5	%

As of September 30, 2019, amounts pertaining to expected income tax refunds of $2 million and $2 million are included in “Income taxes and other current assets” and “Other assets” in the consolidated balance sheets, respectively.

Frontier considered positive and negative evidence in regard to evaluating certain deferred tax assets during the third quarter of 2019, including the development of recent years of pre-tax book losses. On the basis of this evaluation, a valuation allowance of $141 million ($113 million net of federal benefit) has been recorded for the nine months ended September 30, 2019, related to these deferred tax assets and reflected in “Changes in certain deferred tax balances.” The amount of the deferred tax assets considered realizable, however, could be adjusted if estimates of future taxable income during the carryforward period are reduced or increased or if objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as our projections for growth.

As of December 31, 2018, Frontier had approximately $2.4 billion of federal NOLs, which for U.S. federal income tax purposes can be used to offset future taxable income. The closing of the sale of the Northwest Operations would utilize approximately $1 billion of these NOLs.