Earnings per share

Basic earnings per share is computed by dividing net income available to Sirius Group common shareholders by the weighted-average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income (loss) available to Sirius Group common shareholders on a diluted basis by the weighted-average number of common shares outstanding adjusted to give effect to potentially dilutive securities.

The Series B preference shares qualify as participating securities, which requires the application of the two-class method to compute both basic and diluted earnings per share. The two-class method is an earnings allocation formula that treats participating securities as having rights to earnings that would otherwise have been available to common shareholders. The Series B preference shares have no obligation to absorb losses of the Company in periods of net loss.

The following table sets forth the computation of basic and diluted earnings per common share for the three and six months ended June 30, 2020 and 2019:



	For the three months ended June 30,						For the six months ended June 30,
(Millions, except share and per share information)	2020			2019			2020			2019
Basic earnings per share
Numerator:
Net income	$	(7.2	)	$	8.2		$	(128.5	)	$	112.3
Less: Income attributable to non-controlling interests	0.2			(0.8		)	—			(1.2		)
Less: Change in carrying value of Series B preference shares	(6.6		)	(0.8		)	16.8			(9.2		)
Net income available for dividends out of undistributed earnings	$	(13.6	)	$	6.6		$	(111.7	)	$	101.9
Less: Earnings attributable to Series B preference shares	—			(0.6		)	—			(9.5		)
Net income available to Sirius Group common shareholders	$	(13.6	)	$	6.0		$	(111.7	)	$	92.4
Denominator:
Weighted average shares outstanding for basic earnings per share	115,278,176			115,243,685			115,269,720			115,212,772
Basic earnings per share	$	(0.12	)	$	0.05		$	(0.97	)	$	0.80
Diluted earnings per share
Numerator:
Net income available to Sirius Group common shareholders	$	(13.6	)	$	6.0		$	(111.7	)	$	92.4
Add: Change in carrying value of Series B preference shares	—			—			(16.8		)	9.2
Net income available to Sirius Group common shareholders on a diluted basis	$	(13.6	)	$	6.0		$	(128.5	)	$	101.6
Denominator:
Weighted average shares outstanding for basic earnings per share	115,278,176			115,243,685			115,269,720			115,212,772
Add: Series B preference shares	—			—			11,901,670			11,901,670
Add: Unvested performance share units and restricted share units	—			552,682			—			427,960
Weighted average shares outstanding for diluted earnings per share⁽¹⁾	115,278,176			115,796,367			127,171,390			127,542,402
Diluted earnings per share	$	(0.12	)	$	0.05		$	(1.01	)	$	0.80

⁽¹⁾For the three months ended June 30, 2020, there were a total of 27,825,191 potentially dilutive securities excluded from the calculation of Diluted earnings per share. For the three months ended June 30, 2019, there were 30,933,781 potentially dilutive securities excluded from the calculation of Diluted earnings per share. For the six months ended June 30, 2020, there were a total of 15,923,521 potentially dilutive securities excluded from the calculation of Diluted earnings per share. For the six months ended June 30, 2019, there were 19,156,833 potentially dilutive securities excluded from the calculation of Diluted earnings per share.