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 2.8 million, 2.1 million, and 2.3 million for the years ended December 31, 2014, 2013, and 2012, 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)	2014			2013			2012
Earnings per common share calculation – basic
Income from continuing operations attributable to common shareholders	$	292,089		$	151,594		$	154,116
Amount allocated to participating securities	(2,687		)	(3,177		)	(2,784		)
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	$	289,402		$	148,417		$	151,332
Discontinued operations, including gain on sale, attributable to common shareholders	—			184,770			129,274
Net income attributable to common shareholders – basic	$	289,402		$	333,187		$	280,606

Earnings per common share from continuing operations	$	3.29		$	1.70		$	1.81
Earnings per common share from discontinued operations	—			2.12			1.54
Total earnings per common share – basic	$	3.29		$	3.82		$	3.35

Weighted average number of common shares outstanding – basic	88,084			87,204			83,772



	Year Ended December 31,
(in thousands, except per share amounts)	2014		2013		2012
Earnings per common share calculation – diluted
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	$	289,402	$	148,417	$	151,332
Income allocated to common units from continuing operations	—		1,133		1,984
Income from continuing operations attributable to common shareholders, as adjusted	$	289,402	$	149,550	$	153,316
Discontinued operations, including gain on sale, attributable to common shareholders	—		184,770		129,274
Net income attributable to common shareholders – diluted	$	289,402	$	334,320	$	282,590

Earnings per common share from continuing operations	$	3.27	$	1.69	$	1.79
Earnings per common share from discontinued operations	—		2.09		1.51
Total earnings per common share – diluted	$	3.27	$	3.78	$	3.30

Weighted average number of common shares outstanding – basic	88,084		87,204		83,772
Incremental shares issuable from assumed conversion of:
Common share options and share awards granted	384		476		647
Common units	—		814		1,137
Weighted average number of common shares outstanding – diluted	88,468		88,494		85,556