Earnings Per Share

The Company calculates basic earnings per common share by dividing net income attributable to the Company's common stockholders for the period by weighted-average shares of common stock outstanding for that period. Diluted earnings per common share takes into account the effect of dilutive instruments, such as convertible notes and performance share awards, and the number of incremental shares that are to be added to the weighted-average number of shares outstanding.

During the years ended December 31, 2018 and December 31, 2017, the Company's Convertible Notes were determined to be dilutive and were included in the calculation of diluted earnings per common share under the "if-converted" method. Under this method, the periodic interest expense (net of applicable taxes) for dilutive notes is added back to the numerator and the number of shares that the notes are entitled to (if converted, regardless of whether they are in or out of the money) are included in the denominator. During the year ended December 31, 2018, PSUs awarded under the Company's 2018 Long-Term Equity Incentive Program ("2018 Long-Term EIP") (see Note 21) were also determined to be dilutive and were included in the calculation of diluted earnings per common share under the treasury stock method. Under this method, common equivalent shares are calculated assuming that target PSUs vest according to the PSU Agreements and unrecognized compensation cost is used to repurchase shares of the Company’s outstanding common stock at the average market price during the reported period. There were no dilutive PSU awards during the year ended December 31, 2017. There were no dilutive instruments for the year ended December 31, 2016.

The following table presents the computation of basic and diluted earnings per common share for the periods indicated (dollar and share amounts in thousands, except per share amounts):



	Twelve Months Ended December 31,
	2018			2017			2016
Basic Earnings per Common Share
Net income attributable to Company	$	102,886		$	91,980		$	67,551
Less: Preferred stock dividends	(23,700		)	(15,660		)	(12,900		)
Net income attributable to Company's common stockholders	$	79,186		$	76,320		$	54,651
Basic weighted average common shares outstanding	127,243			111,836			109,594
Basic Earnings per Common Share	$	0.62		$	0.68		$	0.50

Diluted Earnings per Common Share:
Net income attributable to Company	$	102,886		$	91,980		$	67,551
Less: Preferred stock dividends	(23,700		)	(15,660		)	(12,900		)
Add back: Interest expense on convertible notes for the period, net of tax	10,475			9,158			—
Net income attributable to Company's common stockholders	$	89,661		$	85,478		$	54,651
Weighted average common shares outstanding	127,243			111,836			109,594
Net effect of assumed convertible notes conversion to common shares	19,695			18,507			—
Net effect of assumed PSUs vested	512			—			—
Diluted weighted average common shares outstanding	147,450			130,343			109,594
Diluted Earnings per Common Share	$	0.61		$	0.66		$	0.50