Income Taxes	3 Months Ended
Sep. 30, 2017
Income Taxes
Income Taxes	10. Income Taxes The provision for income taxes is determined using an effective tax rate that is subject to fluctuations during the year as new information is obtained. The assumptions used to estimate the annual effective tax rate include factors such as the mix of pre-tax earnings in the various tax jurisdictions in which we operate, valuation allowances against deferred tax assets, increases or decreases in uncertain tax positions, utilization of research and development tax credits, changes in or the interpretation of tax laws in jurisdictions where we conduct business and certain tax elections. We recognize deferred tax assets and liabilities for temporary differences between the financial reporting basis and the tax basis of our assets and liabilities along with net operating loss and tax credit carryovers. We record a valuation allowance against our deferred tax assets to reduce the net carrying value to an amount that we believe is more likely than not to be realized. When we establish or reduce the valuation allowance against our deferred tax assets, the provision for income taxes will increase or decrease in the period such determination is made. We believe it is more likely than not that a portion of the Company’s deferred income tax assets, for which no valuation allowance has been recorded, may expire unused. Accordingly, during the three months ended September 30, 2017, we increased our valuation allowance by $5.3 million. The impact of the increase in valuation allowance was partially offset by a tax benefit for equity-based compensation of $4.3 million under ASU 2016-09 during the quarter resulting in an effective tax rate of 32.9%. Excluding the net impact of these discrete tax items, our effective tax rate for the three months ended September 30, 2017 was 28.3% as compared to 28.0% for the comparable prior-year period.

10. Income Taxes

The provision for income taxes is determined using an effective tax rate that is subject to fluctuations during the year as new information is obtained. The assumptions used to estimate the annual effective tax rate include factors such as the mix of pre-tax earnings in the various tax jurisdictions in which we operate, valuation allowances against deferred tax assets, increases or decreases in uncertain tax positions, utilization of research and development tax credits, changes in or the interpretation of tax laws in jurisdictions where we conduct business and certain tax elections. We recognize deferred tax assets and liabilities for temporary differences between the financial reporting basis and the tax basis of our assets and liabilities along with net operating loss and tax credit carryovers. We record a valuation allowance against our deferred tax assets to reduce the net carrying value to an amount that we believe is more likely than not to be realized. When we establish or reduce the valuation allowance against our deferred tax assets, the provision for income taxes will increase or decrease in the period such determination is made. We believe it is more likely than not that a portion of the Company’s deferred income tax assets, for which no valuation allowance has been recorded, may expire unused. Accordingly, during the three months ended September 30, 2017, we increased our valuation allowance by $5.3 million. The impact of the increase in valuation allowance was partially offset by a tax benefit for equity-based compensation of $4.3 million under ASU 2016-09 during the quarter resulting in an effective tax rate of 32.9%. Excluding the net impact of these discrete tax items, our effective tax rate for the three months ended September 30, 2017 was 28.3% as compared to 28.0% for the comparable prior-year period.