EARNINGS PER COMMON SHARE

Basic earnings per common share is computed using the two-class method by dividing net income attributable to common stockholders by the weighted average number of common shares outstanding during the period. All outstanding unvested restricted stock awards contain rights to non-forfeitable dividends and participate in undistributed earnings with common stockholders; accordingly, they are considered participating securities that are included in the two-class method. Diluted earnings per common share measures the performance of the Company over the reporting period while giving effect to all potential common shares that were dilutive and outstanding during the period. The denominator includes the weighted average number of basic shares and the number of additional common shares that would have been outstanding if the potential common shares that were dilutive had been issued, and is calculated using either the two-class, treasury stock or as if-converted method, whichever is most dilutive. Potential common shares are securities (such as options, convertible debt, Series A Participating Redeemable Preferred Units (“Series A Units”), Series B Redeemable Preferred Units (“Series B Units”), Series C Convertible Redeemable Preferred Units (“Series C Units”), Series D Redeemable Preferred Units (“Series D Units”) and common Operating Partnership units (“OP Units”)) that do not have a current right to participate in earnings of the Company but could do so in the future by virtue of their option, redemption or conversion right.

In computing the dilutive effect of convertible securities, net income is adjusted to add back any changes in earnings in the period associated with the convertible security. The numerator also is adjusted for the effects of any other non-discretionary changes in income or loss that would result from the assumed conversion of those potential common shares. In computing diluted earnings per common share, only potential common shares that are dilutive (those that reduce earnings per common share) are included. For the three months ended March 31, 2018 and 2017, options to purchase approximately 40,956 and 103,854 shares of common stock, respectively, were excluded from the computation of earnings per share as their effect would have been anti-dilutive.

For the purposes of computing the diluted impact of the potential exchange of the Preferred Operating Partnership units for common shares upon redemption, where the Company has the option to redeem in cash or shares and where the Company has stated the intent and ability to settle the redemption in shares, the Company divided the total value of the Preferred Operating Partnership units by the average share price for the period presented. The average share price for the three months ended March 31, 2018 and 2017 was $84.11 and $75.47, respectively.

The following table presents the number of Preferred Operating Partnership units, and the potential common shares, that were excluded from the computation of earnings per share as their effect would have been anti-dilutive.



	For the Three Months Ended March 31,
	2018	2017
	Equivalent Shares (if converted)	Equivalent Shares (if converted)
Series B Units	498,183	555,216
Series C Units	352,385	392,727
Series D Units	1,094,555	1,071,983
	1,945,123	2,019,926

The Operating Partnership had $11,555 of its 2.375% Exchangeable Senior Notes due 2033 (the “2013 Notes”) issued and outstanding as of March 31, 2018. The 2013 Notes could potentially have a dilutive impact on the Company’s earnings per share calculations. The 2013 Notes are exchangeable by holders into shares of the Company’s common stock under certain circumstances per the terms of the indenture governing the 2013 Notes. The exchange price of the 2013 Notes was $52.82 per share as of March 31, 2018, and could change over time as described in the indenture. The Company has irrevocably agreed to pay only cash for the accreted principal amount of the 2013 Notes relative to its exchange obligations, but retained the right to satisfy the exchange obligation in excess of the accreted principal amount in cash and/or common stock.

The Operating Partnership had $575,000 of its 3.125% Exchangeable Senior Notes due 2035 (the “2015 Notes”) issued and outstanding as of March 31, 2018. The 2015 Notes could potentially have a dilutive impact on the Company’s earnings per share calculations. The 2015 Notes are exchangeable by holders into shares of the Company’s common stock under certain circumstances per the terms of the indenture governing the 2015 Notes. The exchange price of the 2015 Notes was $93.60 per share as of March 31, 2018, and could change over time as described in the indenture. The Company has irrevocably agreed to pay only cash for the accreted principal amount of the 2015 Notes relative to its exchange obligations, but retained the right to satisfy the exchange obligation in excess of the accreted principal amount in cash and/or common stock.

Although the Company has retained the right to satisfy the exchange obligation in excess of the accreted principal amount of the 2013 Notes and 2015 Notes in cash and/or common stock, Accounting Standards Codification (“ASC”) 260, “Earnings per Share,” requires an assumption that shares would be used to pay the exchange obligation in excess of the accreted principal amount, and requires that those shares be included in the Company’s calculation of weighted average common shares outstanding for the diluted earnings per share computation. For the three months ended March 31, 2018 and 2017, 81,382 and 336,848 shares, respectively, related to the 2013 Notes were included in the computation for diluted earnings per share. For the three months ended March 31, 2018 and 2017, no shares related to the 2015 Notes were included in the computation for diluted earnings per share as the exchange price exceeded the per share price of the Company’s common stock during these periods.

For the purposes of computing the diluted impact on earnings per share of the potential exchange of Series A Units for common shares upon redemption, where the Company has the option to redeem in cash or shares and where the Company has stated the positive intent and ability to settle at least $101,700 of the instrument in cash (or net settle a portion of the Series A Units against the related outstanding note receivable), only the amount of the instrument in excess of $101,700 is considered in the calculation of shares contingently issuable for the purposes of computing diluted earnings per share as allowed by ASC 260-10-45-46. Accordingly, the number of shares included in the computation for diluted earnings per share related to the Series A Units is equal to the number of Series A Units outstanding, with no additional shares included related to the fixed $101,700 amount.

The computation of earnings per common share was as follows for the periods presented:



	For the Three Months Ended March 31,
	2018			2017
Net income attributable to common stockholders	$	88,256		$	82,282
Earnings and dividends allocated to participating securities	(178		)	(197		)
Earnings for basic computations	88,078			82,085
Earnings and dividends allocated to participating securities	178			—
Income allocated to noncontrolling interest - Preferred Operating Partnership Units and Operating Partnership Units	4,941			4,049
Fixed component of income allocated to noncontrolling interest - Preferred Operating Partnership (Series A Units)	(572		)	(1,271		)
Net income for diluted computations	$	92,625		$	84,863

Weighted average common shares outstanding:
Average number of common shares outstanding - basic	125,772,439			125,605,403
OP Units	5,663,370			5,596,191
Series A Units	875,480			875,480
Shares related to exchangeable senior notes and dilutive stock options	371,271			541,570
Average number of common shares outstanding - diluted	132,682,560			132,618,644
Earnings per common share
Basic	$	0.70		$	0.65
Diluted	$	0.70		$	0.64