INCOME TAXES

The components of the provision for income taxes are shown below for the periods presented (in thousands):



	Three months ended March 31,
	2017		2016
Current:
U.S. federal	$	—	$	—
State	—		11
Provision for income taxes	$	—	$	11

As a result of the operating loss incurred during the three months ended March 31, 2017, and after the application of the annual limitation set forth under Section 382 of the Internal Revenue Code (“IRC”), it was not necessary to record a provision for U.S. federal income tax or various states income taxes. The expense recorded for the three months ended March 31, 2016, represents the adjustment of the 2015 provision to the actual tax on the 2015 returns.

At March 31, 2017 and December 31, 2016, we had a full valuation allowance recorded against our deferred tax assets. The valuation allowance was recorded due to uncertainties related to our ability to realize the deferred tax assets, primarily consisting of certain net operating loss carry-forwards. The valuation allowance is based on management’s estimates of taxable income by jurisdiction and the periods over which the deferred tax assets will be recoverable.

At December 31, 2016, we had a net operating loss carry-forward of approximately $79.8 million for U.S. federal, state, and local income tax purposes. However, due to changes in our capital structure, approximately $25.4 million of the net operating loss carry-forward is available to offset future taxable income, and after the application of the limitations found under Section 382 of the IRC, we only expect to have approximately $18.5 million of this amount available for use in 2017. If not used, these carry-forwards will begin to expire in 2021 for federal and in 2021 or sooner for state and local purposes. For a full discussion of the estimated restrictions on our utilization of net operating loss carry-forwards, please refer to Note 10, “Income Taxes,” included under Item 8 of our 2016 Annual Report.