18.	Incentive Compensation

Stock-Based Compensation

We account for all stock-based compensation in accordance with ASC Topic 718, Compensation – Stock Compensation. As of September 30, 2017, we have 10,369,943 shares available for future grants under the 2014 Equity Incentive Plan (“Plan”), if all awards granted are full value awards, as defined in the Plan. Stock-based compensation expense was $3,825,000 and $2,583,000 for the three months ended September 30, 2017 and 2016, respectively, and $11,692,000 and $8,766,000 for the nine months ended September 30, 2017 and 2016, respectively. Stock-based compensation expense for the nine months ended September 30, 2016 includes $1,855,000 of expense related to the acceleration of vesting of stock awards in connection with a separation agreement.

2017 Performance Program

On January 30, 2017, the Compensation Committee approved the 2017 Performance Program, a multiyear performance-based long-term equity (“LTE”) compensation program. The purpose of the 2017 Performance Program is to further align the interests of our stockholders with that of management by encouraging our senior officers to create stockholder value in a “pay for performance” structure. Under the 2017 Performance Program, participants may earn awards in the form of Long Term Incentive Plan (“LTIP”) units of our Operating Partnership based on our Total Shareholder Return (“TSR”) over a three-year performance measurement period beginning on January 1, 2017 and continuing through December 31, 2019, on both an absolute basis and relative basis. 25.0% of the award is earned if we outperform a predetermined absolute TSR and the remaining 75.0% is earned if we outperform a predetermined relative TSR. Specifically, participants begin to earn awards under the 2017 Performance Program if our TSR for the performance measurement period equals or exceeds 18.0% on an absolute basis and is in the 30th percentile of the performance of the SNL Office REIT Index constituents on a relative basis, and awards will be fully earned if our TSR for the performance measurement period equals or exceeds 30.0% on an absolute basis and exceeds the 80^th percentile of the performance of the SNL Office REIT Index constituents on a relative basis. Participants will not earn any awards under the 2017 Performance Program if our TSR during the performance measurement period does not meet either of these minimum thresholds. The number of LTIP units that are earned if performance is above the minimum thresholds, but below the maximum thresholds, will be determined based on linear interpolation between the percentages earned at the minimum and maximum thresholds. During the performance measurement period, participants will receive per unit distributions equal to one-tenth of the per share dividends otherwise payable to our common stockholders with respect to their LTIP units. If the LTIP units are ultimately earned based on the achievement of the designated performance objectives, participants will receive cash or additional LTIP units based on the additional amount the participants would have received if per unit distributions during the performance measurement periods for the earned LTIP units had equaled per share dividends paid to our common stockholders less the amount of distributions participants actually received during the performance measurement period.

If the designated performance objectives are achieved, awards earned under the 2017 Performance Program will also be subject to vesting based on continued employment with us through December 31, 2020, with 50.0% of each award vesting following the conclusion of the performance measurement period, and the remaining 50.0% vesting on December 31, 2020. The Company’s named executive officers, as defined, are required to hold earned awards for an additional one-year following vesting. The fair value of the awards granted under the 2017 Performance Program on the date of the grant was $10,520,000 and is being amortized into expense over the four-year vesting period using a graded vesting attribution method.