15.

INCOME TAXES: The effective tax rate for the first quarter of 2017 was 31.2% compared to 27.8% for the first quarter of 2016. The increase in the effective tax rate for the first quarter of 2017 as compared to the first quarter of 2016 is primarily due to the change in relative proportions of net earnings attributable to noncontrolling interests to total pre-tax earnings between the periods. The increase in effective tax rate is also due to a $4.5 million favorable non-cash out-of-period adjustment to current tax balances during the first quarter of 2016.

Nucor has concluded U.S. federal income tax matters for years through 2012. The tax years 2013 through 2015 remain open to examination by the Internal Revenue Service. The Canada Revenue Agency has substantially concluded its examination of the 2012 Canadian returns for Harris Steel Group Inc. and certain related affiliates and is now examining the 2013 Canadian returns. The tax years 2009 through 2015 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 liabilities included in deferred credits and other liabilities in the condensed consolidated balance sheets were $546.5 million at April 1, 2017 ($558.6 million at December 31, 2016).