5.Income Taxes

Effective Tax Rate

For the three months ended March 31, 2016 and March 31, 2015, we recorded no income tax expense or benefit, resulting in an effective tax rate of 0%. The significant difference between our effective tax rate and the federal statutory income tax rate of 35% is due to a full valuation allowance recorded on net deferred tax assets in excess of deferred tax liabilities. A valuation allowance is established to reduce deferred tax assets when it is more likely than not that some portion or all of the deferred tax asset will not be realized. As of March 31, 2016 and December 31, 2015, the Company believes it is more likely than not that the overall deferred tax asset will not be realized. As of March 31, 2016, the Company did not have any uncertain tax positions requiring adjustments to its liability.