7.Income Taxes

Our income tax provision for the periods presented and the respective effective income tax rates for such periods are as follows (in millions, except for income tax rates):


	For the Three Months ended
	March 31,
	2016			2015
Income tax provision	$	4.8		$	9.9

Effective income tax rate		8.3	%		15.3	%

Our provision for income taxes for each of the three-month periods ended March 31, 2016 and 2015 was calculated based on the estimated annual effective income tax rate for the full 2016 and 2015 fiscal years. Our provision for income taxes for the first quarter of 2016 was adjusted for an income tax benefit of $4.0 million, net for discrete items related to changes in estimates in uncertain tax positions. Without the $4.0 million adjustment, the first quarter of 2016 effective income tax rate would have been 15.4%. The actual effective income tax rate for the full 2016 fiscal year may be materially different as a result of differences between estimated versus actual results and the geographic tax jurisdictions in which the results are earned.

We operated under a special income tax concession in Singapore which began January 1, 2008. Our current five year special income tax concession was effective January 1, 2013. The special income tax concession is conditional upon our meeting of certain employment and investment thresholds which, if not met in accordance with our agreement, may eliminate the benefit beginning with the first year in which the conditions are not satisfied. The income tax concession reduces the income tax rate on qualified sales and the impact of this income tax concession decreased foreign income taxes by $0.6 million and $2.3 million for the three months ended March 31, 2016 and 2015, respectively. The impact of the income tax concession on basic earnings per common share was $0.01 and $0.03 for the three months ended March 31, 2016 and 2015, respectively. On a diluted earnings per common share basis, the impact was $0.01 and $0.03 for the three months ended March 31, 2016 and 2015, respectively.