The following table sets forth the computation of basic and diluted earnings per common share:



	Three Months Ended June 30,						Six Months Ended June 30,
	2020			2019			2020			2019
	($ in thousands except share and per share data)
Numerator:
Net income (loss) before preference dividends	$	189,937		$	18,733		$	(76,671	)	$	71,272
Preference dividends	(1,109		)	(4,908		)	(2,280		)	(9,815		)
Net income (loss) available to common shareholders	188,828			13,825			(78,951		)	61,457

Denominator:
Weighted average common shares outstanding - basic	19,863,048			22,740,762			19,907,490			22,711,833
Effect of dilutive common share equivalents:
Weighted average non-vested restricted share units (1)(2)	—			6,271			—			3,136
Weighted average common shares outstanding - diluted (3)	19,863,048			22,747,033			19,907,490			22,714,969
Earnings (loss) per common share:
Basic and diluted	$	9.51		$	0.61		$	(3.97	)	$	2.71

(1) During the three months ended June 30, 2020, the Company issued 100,958 common shares, relating to restricted share units granted in the second quarter of 2019. Of these shares, 27,456 common shares vested during the three months ended June 30, 2020.

(2) During the three months ended June 30, 2020, the Company did not grant any restricted share units or common shares. During the six months ended June 30, 2020 and June 30, 2019, the Company granted an aggregate of 63,591 and 165,287, respectively, of restricted share units and common shares to certain employees and directors. Of the total restricted share units and common shares granted, 103,820 are non-vested as of June 30, 2020. The weighted average non-vested restricted share units of 6,864 are excluded from the calculation of diluted weighted average common shares outstanding for the six months ended June 30, 2020, due to a net loss reported. Refer to Note 17, “Share transactions” for further details.

(3) Warrants held by Arch and HPS were not included in the computation of diluted earnings because the exercise price of the warrants exceeded the market price of the common shares during the period and the exercise of the warrants would have been anti-dilutive. The warrants expired on March 25, 2020. The number of common shares issuable upon exercise of the warrants that was excluded was 1,704,691 common shares.