A reconciliation of the U.S. federal statutory tax rate to the Company’s effective income tax rate is as follows:

The effective income tax rates in all periods were impacted by recognition of net discrete tax benefits related to employee stock-based compensation payments. In fiscal 2019, the effective income tax rate included discrete tax expense for changes in tax reserves and the revaluation of deferred tax balances for legislative updates. In fiscal 2018, as a result of the Tax Act, we recorded a non-recurring net tax benefit for the revaluation of our net deferred tax liabilities.

The Tax Act made broad and complex changes to U.S. federal corporate income taxation including, but not limited to: (i) reducing the statutory corporate tax rate from 35% to 21% (a blended statutory tax rate of 29.2% for fiscal 2018); (ii) repeal of the Section 199 qualified production activities deduction; (iii) creating new or furthering limitations to the deductibility of certain officer compensation, interest, meals, entertainment and other expenses; and (iv) changing from a worldwide to a territorial taxation system. As of May 31, 2019, the Company’s accounting for the impact of the Tax Act was completed.

As a result of the Tax Act, the Company derived estimated tax benefits of $160.5 million, including a net tax benefit of $83.5 million related to the revaluation of the Company’s net deferred tax liabilities and a net tax benefit of $77.0 million related to the reduction in the Company’s statutory income tax rate for fiscal 2018 applied to income before taxes. These amounts totaled $0.23 per diluted share and $0.21 per diluted share, respectively.

Uncertain income tax positions:  The Company is subject to U.S. federal income tax, numerous local and state tax jurisdictions within the U.S., and taxes in Europe. The Company maintains a reserve for uncertain tax positions. As of May 31, 2020 and May 31, 2019, the total reserve for uncertain tax positions, including interest and net of federal benefits, was $26.5 million and $21.6 million, respectively, and was included in long-term liabilities on the Consolidated Balance Sheets.

A reconciliation of the beginning and ending amounts of the Company’s gross unrecognized tax benefits, not including interest or other potential offsetting effects, is as follows:

In May 2018, the Company settled its IRS examination for fiscal 2012 through fiscal 2017. As a result of the settlement, the reserve for uncertain tax positions was decreased by $27.2 million and income tax expense of $2.7 million was recorded.

The reserve as of May 31, 2020 substantially relates to the Company’s uncertain tax positions for certain state income tax matters. The Company believes the reserve for uncertain tax positions, including interest and net of federal benefits, of $26.5 million as of May 31, 2020 adequately covers open tax years and uncertain tax positions up to and including fiscal 2020 for major taxing jurisdictions. As of May 31, 2020 and May 31, 2019, the entire $26.5 million and $21.6 million, respectively, of unrecognized tax benefits, including interest and net of federal benefit, if recognized, would impact the Company’s effective income tax rate.