9. Equity Incentive Plan

The Company’s Board of Directors has adopted and, with the approval of the Company’s stockholders, amended the 2010 Equity Incentive Plan (as amended, the “2010 Plan”). The 2010 Plan is administered by the Compensation Committee of the Board of Directors. Awards issuable under the 2010 Plan include common stock, stock options, restricted stock, stock appreciation rights, dividend equivalents, Operating Partnership units and other incentive awards. We have reserved a total of 6,000,000 shares of our common stock for issuance pursuant to the 2010 Plan, which may be adjusted for changes in our capitalization and certain corporate transactions. To the extent that an award expires, terminates or lapses, or an award is settled in cash without the delivery of shares of common stock to the participant, then any unexercised shares subject to the award will be available for future grant or sale under the 2010 Plan. Shares of restricted stock which are forfeited or repurchased by us pursuant to the 2010 Plan may again be awarded under the 2010 Plan. The payment of dividend equivalents in cash in conjunction with any outstanding awards will not be counted against the shares available for issuance under the 2010 Plan.

As of March 31, 2015, 3,318,347 shares of our common stock were available for issuance pursuant to the 2010 Plan.

Stock Options

Stock option awards are granted with an exercise price equal to the closing market price of the Company’s common stock on the date of grant. The fair value of each option granted under the 2010 Plan is estimated on the date of grant using the Black-Scholes option-pricing model. The fair values are amortized on a straight-line basis over the vesting periods.

The following table sets forth stock option activity under the 2010 Plan for the three months ended March 31, 2015:

	Number of Shares Subject to Options		Weighted- Average Exercise Price
Options outstanding, December 31, 2014	758,095		$	20.94
Granted	—		—
Exercised	(20,287	)	22.13
Forfeited	(562	)	15.23
Expired	(282	)	15.23
Options outstanding, March 31, 2015	736,964		$	20.91

The following table sets forth the number of shares subject to options that are unvested as of March 31, 2015, and the fair value of these options at the grant date:

	Number of Shares Subject to Options		Weighted- Average Fair Value at Grant Date
Unvested balance, December 31, 2014	283,964		$	7.75
Granted	—		—
Forfeited	(562	)	4.89
Vested	(116,780	)	6.43
Unvested balance, March 31, 2015	166,622		$	8.67

As of March 31, 2015, total unearned compensation on options was approximately $1.0 million, and the weighted-average vesting period was 1.4 years.

Restricted Awards and Units

During the three months ended March 31, 2015, the Company granted 176,269 shares of restricted stock which had a fair value of $8.4 million as of the date of grant. Also during the three months ended March 31, 2015, the Company issued 428 restricted stock units, or RSUs. The principal difference between these instruments is that RSUs are not shares of the Company’s common stock and do not have any of the rights or privileges thereof, including voting rights. On the applicable vesting date, the holder of an RSU becomes entitled to a share of common stock. The restricted stock awards are amortized on a straight-line basis to expense over the vesting period. The following table sets forth the number of unvested restricted stock and RSU awards and the weighted-average fair value of these awards at the date of grant:

	Restricted Awards		Weighted- Average Fair Value at Grant Date
Unvested balance, December 31, 2014	394,016		$	29.10
Granted	176,697		47.49
Forfeited	(2,749	)	28.17
Vested	(111,143	)	27.24
Unvested balance, March 31, 2015	456,821		$	36.67

As of March 31, 2015, total unearned compensation on restricted awards was approximately $15.1 million, and the weighted-average vesting period was 2.5 years.

Performance Stock Awards

The Company grants long-term incentives to members of management in the form of performance-based restricted stock awards (“PSAs”) under the 2010 Plan. The number of PSAs earned is based on the Company’s achievement of relative total shareholder return (“TSR”) measured versus the MSCI US REIT Index over a three-year performance period, and the number of shares earned under the PSAs may range from 0% to 150% for 2014 grants and from 25% to 175% for 2015 grants. The PSAs are earned as follows: (i) 20% of the PSAs are eligible to be earned upon TSR achievement in year one of the performance period, (ii) 20% of the PSAs are eligible to be earned upon TSR achievement in year two of the performance period, (iii) 20% of the PSAs are eligible to be earned upon TSR achievement in year three of the performance period, and (iv) 40% of the PSAs are eligible to be earned upon a cumulative TSR achievement over the three-year performance period. The PSAs have a service condition and will be released at the end of the three-year performance period provided that the holder continues to be employed by the Company at the end of the three-year performance period. Holders of the PSAs are entitled to dividends on the PSAs, which will be accrued and paid in cash at the end of the three-year performance period. The PSAs initially are granted and issued at the highest target amount and thereafter are forfeited to the extent vesting conditions are not met.

On March 4, 2014, the Company granted 91,335 PSAs equal to 150% of the target amount, with an aggregate value of $1.6 million on the grant date. The PSAs, in addition to a service condition, are subject to the Company’s performance versus the MSCI US REIT Index which is a market condition and impacts the number of shares that ultimately vests. Upon evaluating the results of the market condition, the final number of shares is determined and such shares vest based on satisfaction of the service condition. The PSAs are amortized on a straight-line basis over the vesting period. During the three months ended March 31, 2015, no PSAs were forfeited due to termination of service.

On March 3, 2015, the Company granted 78,551 PSAs equal to 175% of the target amount, with an aggregate value of $2.7 million on the grant date. The PSAs, in addition to a service condition, are subject to the Company’s performance versus the MSCI US REIT Index which is a market condition and impacts the number of shares that ultimately vests. Upon evaluating the results of the market condition, the final number of shares is determined and such shares vest based on satisfaction of the service condition. The PSAs are amortized on a straight-line basis over the vesting period. During the three months ended March 31, 2015, no PSAs were forfeited due to termination of service.

As of March 31, 2015, total unearned compensation on PSAs was approximately $3.6 million, and the weighted-average vesting period was 2.4 years. The fair value of each PSA award is estimated on the date of grant using a Monte Carlo simulation. The simulation requires assumptions for expected volatility, risk-free rate of return, and dividend yield. The following table summarizes the assumptions used to value the PSAs granted during the three months ended March 31, 2015, and 2014.

	Three Months Ended March 31,
	2015		2014
Expected term (in years)	2.83		2.83
Expected volatility	25.51	%	32.98	%
Expected annual dividend	—		—
Risk-free rate	1.02	%	0.64	%