4.	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 June 30, 2015 and 2014, options to purchase approximately 44,207 and 33,059 shares of common stock, respectively, and for the six months ended June 30, 2015 and 2014, options to purchase 32,193 and 25,068 shares of common stock, respectively, were excluded from the computation of earnings per share as their effect would have been anti-dilutive.

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, assuming full conversion.


	For the Three Months Ended June 30, 2015				For the Three Months Ended June 30, 2014
	Number of Units		Equivalent Shares (if converted)		Number of Units		Equivalent Shares (if converted)
Series B Units		1,676,087		618,026		1,668,760		809,292
Series C Units		704,016		437,154		600,656		490,545
Series D Units		548,390		202,209		—		—

		2,928,493		1,257,389		2,269,416		1,299,837


	For the Six Months Ended June 30, 2015				For the Six Months Ended June 30, 2014
	Number of Units		Equivalent Shares (if converted)		Number of Units		Equivalent Shares (if converted)
Series B Units		1,676,087		628,124		1,506,644		768,853
Series C Units		704,016		444,297		504,858		433,854
Series D Units		548,390		205,513		—		—

		2,928,493		1,277,934		2,011,502		1,202,707

The Operating Partnership had $250,000 of its 2.375% Exchangeable Senior Notes due 2033 (the “Notes”) issued and outstanding as of June 30, 2015. The Notes could potentially have a dilutive impact on the Company’s earnings per share calculations. The Notes are exchangeable by holders into shares of the Company’s common stock under certain circumstances per the terms of the indenture governing the Notes. The exchange price of the Notes was $55.26 per share as of June 30, 2015, 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 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.

Though the Company has retained that right, 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 and six months ended June 30, 2015, 836,630 shares related to the Notes were included in the computation for diluted earnings per share. For the three and six months ended June 30, 2014, no shares related to the 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 this period.

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 $115,000 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 $115,000 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.

For the purposes of computing the diluted impact on earnings per share of the potential exchange of Series B 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 Series B Units outstanding as of June 30, 2015 of $41,903 by the closing price of the Company’s common stock as of June 30, 2015 of $65.22 per share.

For the purposes of computing the diluted impact on earnings per share of the potential exchange of Series C 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 Series C Units outstanding as of June 30, 2015 of $29,639 by the closing price of the Company’s common stock as of June 30, 2015 of $65.22 per share.

For the purposes of computing the diluted impact on earnings per share of the potential exchange of Series D 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 Series D Units outstanding as of June 30, 2015 of $13,710 by the closing price of the Company’s common stock as of June 30, 2015 of $65.22 per share.

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


	For the Three Months Ended June 30,						For the Six Months Ended June 30,
	2015			2014			2015			2014
Net income attributable to common stockholders	$	55,339		$	41,665		$	109,081		$	79,005
Earnings and dividends allocated to participating securities		(140	)		(125	)		(259	)		(242	)

Earnings for basic computations		55,199			41,540			108,822			78,763

Income allocated to noncontrolling interest - Preferred Operating Partnership (Series A Units) and Operating Partnership		4,276			3,315			7,911			6,443
Fixed component of income allocated to noncontrolling interest - Preferred Operating Partnership (Series A Units)		(1,271	)		(1,437	)		(2,545	)		(2,875	)

Net income for diluted computations	$	58,204		$	43,418		$	114,188		$	82,331

Weighted average common shares outstanding:
Average number of common shares outstanding - basic		116,861,678			115,653,489			116,491,710			115,546,341
Series A Units		875,480			989,980			875,480			989,980
OP Units		5,642,737			4,334,118			5,007,835			4,334,118
Unvested restricted stock awards included for treasury stock method		—			—			—			—
Shares related to exchangeable senior notes and dilutive stock options		1,095,995			276,635			1,102,216			290,853

Average number of common shares outstanding - diluted		124,475,890			121,254,222			123,477,241			121,161,292

Earnings per common share
Basic	$	0.47		$	0.36		$	0.93		$	0.68
Diluted	$	0.47		$	0.36		$	0.92		$	0.68