Share-based payments (Tables)

12 Months Ended

Dec. 31, 2017

Summary of Terms and Conditions, Relating to the Grants of the Non-vested Stock Award under the Equity Compensation Plan

A summary of the terms and conditions, properly approved by the Compensation Committee of our Board of Directors, relating to the grants of the non-vested stock award under the equity compensation plan is as follows:


Grant date	Number of instruments		Vesting conditions	Contractual life
February, 2013		19,786	15% first three anniversaries	5 years
			25% fourth and 30% fifth anniversary
February, 2015		13,709	One-third every anniversary	3 years
April, 2015		4,915	15% first three anniversaries	5 years
			25% fourth anniversary 30% fifth anniversary
June, 2015		10,920	One-third every anniversary	3 years
June, 2015		4,912	Third anniversary	3 years
June, 2015		6,750	15% first three anniversaries	5 years
			25% fourth anniversary 30% fifth anniversary
December, 2015		429	Third anniversary	3 years
February, 2016		19,012	One-third every anniversary	3 years
February, 2016		147,000	15% first three anniversaries	5 years
			25% fourth anniversary 30% fifth anniversary
February, 2016		63,000	Fifth anniversary	5 years
May, 2016		7,899	15% first three anniversaries	5 years
			25% fourth anniversary 30% fifth anniversary
May, 2016		4,739	One-third every anniversary	3 years
June, 2016		25,280	One-third every anniversary	3 years
June, 2016		7,925	Third anniversary	3 years
September, 2016		6,668	Third anniversary	3 years
September, 2016		5,005	One-third every anniversary	3 years
February, 2017		22,012	One-third every anniversary	3 years
June, 2017		11,980	One-third every anniversary	3 years
June, 2017		2,237	Third anniversary	3 years

Summary of Non-vested Stock Award Activity

A summary of the non-vested stock award activity under the plan as of December 31, 2017 and 2016 with changes during these years is as follows (in number of shares):


	2017			2016			2015
Non-vested as of January 1		333,183			139,962			199,786
Granted		36,229			291,872			36,291
Vested		(62,224	)		(94,208	)		(94,704	)
Forfeited		(3,035	)		(4,443	)		(1,411	)

Non-vested as of December 31		304,153			333,183			139,962

Summary of Options Award Activity

A summary of the options award activity under the plan as of December 31, 2017 and 2016 and changes during the year is as follows (in number of shares):


	2017			2016			2015
Outstanding as of January 1		19,894			20,940			20,940
Exercised		(11,061	)		(1,046	)		—
Forfeited		(8,833	)		—			—

Outstanding as of December 31		—			19,894			20,940