3. Per Share Data

Basic earnings per share are computed using net income attributable to common shareholders and the weighted average number of common shares outstanding. Diluted earnings per share reflect common shares issuable from the assumed conversion of common share options and share awards granted and units convertible into common shares. Only those items having a dilutive impact on our basic earnings per share are included in diluted earnings per share. Our unvested share-based awards are considered participating securities and are reflected in the calculation of basic and diluted earnings per share using the two-class method. The number of common share equivalent securities excluded from the diluted earnings per share calculation was approximately 2.4 million, 2.6 million, and 2.8 million for the years ended December 31, 2016, 2015, and 2014, respectively. These securities, which include common share options and share awards granted and units convertible into common shares, were excluded from the diluted earnings per share calculation as they are anti-dilutive.

The following table presents information necessary to calculate basic and diluted earnings per share for the periods indicated:



	Year Ended December 31,
(in thousands, except per share amounts)	2016			2015			2014
Earnings per common share calculation – basic
Income from continuing operations attributable to common shareholders	$	436,981		$	229,565		$	273,892
Amount allocated to participating securities	(6,304		)	(2,052		)	(2,687		)
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	$	430,677		$	227,513		$	271,205
Discontinued operations, including gain on sale, attributable to common shareholders	382,842			19,750			18,197
Net income attributable to common shareholders – basic	$	813,519		$	247,263		$	289,402

Earnings per common share from continuing operations	$	4.81		$	2.55		$	3.08
Earnings per common share from discontinued operations	4.27			0.22			0.21
Total earnings per common share – basic	$	9.08		$	2.77		$	3.29

Weighted average number of common shares outstanding – basic	89,580			89,120			88,084



Earnings per common share calculation – diluted
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	$	430,677	$	227,513	$	271,205
Discontinued operations, including gain on sale, attributable to common shareholders	382,842		19,750		18,197
Net income attributable to common shareholders – diluted	$	813,519	$	247,263	$	289,402

Earnings per common share from continuing operations	$	4.79	$	2.54	$	3.06
Earnings per common share from discontinued operations	4.26		0.22		0.21
Total earnings per common share – diluted	$	9.05	$	2.76	$	3.27

Weighted average number of common shares outstanding – basic	89,580		89,120		88,084
Incremental shares issuable from assumed conversion of:
Common share options and share awards granted	323		370		384
Weighted average number of common shares outstanding – diluted	89,903		89,490		88,468