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 3.0 million and 1.4 million for the three months ended March 31, 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:



	Three Months Ended
	March 31,
(in thousands, except per share amounts)	2013			2012
Earnings per share calculation – basic
Income from continuing operations attributable to common shareholders	$	30,985		$	53,958
Amount allocated to participating securities	(638		)	(890		)
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	30,347			53,068
Income from discontinued operations, including gain on sale, attributable to common shareholders	32,491			34,800
Net income attributable to common shareholders, as adjusted	$	62,838		$	87,868

Income from continuing operations attributable to common shareholders, as adjusted – per share	$	0.35		$	0.66
Income from discontinued operations, including gain on sale, attributable to common shareholders – per share	0.37			0.44
Net income attributable to common shareholders, as adjusted – per share	$	0.72		$	1.10

Weighted average number of common shares outstanding – basic	86,703			79,885

Earnings per share calculation – diluted
Income from continuing operations attributable to common shareholders, net of amount allocated to participating securities	$	30,347		$	53,068
Income allocated to common units from continuing operations	—			639
Income from continuing operations attributable to common shareholders, as adjusted	30,347			53,707
Income from discontinued operations, including gain on sale, attributable to common shareholders	32,491			34,800
Net income attributable to common shareholders, as adjusted	$	62,838		$	88,507

Income from continuing operations attributable to common shareholders, as adjusted – per share	$	0.35		$	0.65
Income from discontinued operations, including gain on sale, attributable to common shareholders – per share	0.37			0.42
Net income attributable to common shareholders, as adjusted – per share	$	0.72		$	1.07

Weighted average number of common shares outstanding – basic	86,703			79,885
Incremental shares issuable from assumed conversion of:
Common share options and share awards granted	573			679
Common units	—			2,291
Weighted average number of common shares outstanding – diluted	87,276			82,855