12.

INCOME TAXES: The effective tax rate for the first quarter of 2018 was 26.3% compared to 31.2% for the first quarter of 2017. The decrease in the effective tax rate for the first quarter of 2018 as compared to the first quarter of 2017 was primarily due to the permanent lowering of the U.S. corporate federal income tax rate from 35% to 21% effective for the years beginning after December 31, 2017 under the Tax Cuts and Jobs Act (the “Tax Reform Act”). This decrease was somewhat offset by increases in the effective tax rate due to the elimination of the domestic manufacturing deduction under the Tax Reform Act and the write-off of $21.8 million of deferred tax assets due to the change in the tax status of a subsidiary in the first quarter of 2018.

Nucor has concluded U.S. federal income tax matters for years through 2013. The tax years 2014 through 2016 remain open to examination by the Internal Revenue Service. The Canada Revenue Agency has substantially concluded its examination of the 2012 and 2013 Canadian returns for Harris Steel Group Inc. and certain related affiliates. The tax years 2010 through 2016 remain open to examination by other major taxing jurisdictions to which Nucor is subject (primarily Canada and other state and local jurisdictions).

Non-current deferred tax assets included in other assets in the condensed consolidated balance sheets were $0.7 million at March 31, 2018 ($0.6 million at December 31, 2017). Non-current deferred tax liabilities included in deferred credits and other liabilities in the condensed consolidated balance sheets were $359.9 million at March 31, 2018 ($329.3 million at December 31, 2017).