Benefit Plans (Tables)

6 Months Ended

Jun. 30, 2017

The following table summarizes the weighted-average assumptions used to compute the fair value of options granted to employees and members of our board of directors:



	For the Three Months Ended June 30,		For the Six Months Ended June 30,
	2017	2016	2017	2016
Risk-free interest rate	1.6%	1.2%	1.6%	1.2%
Expected life of options — years	4.35	3.79	4.07	3.78
Expected stock price volatility	26%	24%	26%	24%
Expected dividend yield	0.8%	0.0%	0.8%	0.0%

Stock options activity under share-based payment plans

The following table summarizes stock option activity under our share-based plans for the six months ended June 30, 2017:



	Options		Weighted- Average Exercise Price Per Share		Weighted- Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding as of December 31, 2016	332,648		$	3.50
Granted	3,047		$	4.91
Exercised	(21,616	)	$	2.78
Forfeited, cancelled or expired	(2,657	)	$	3.76
Outstanding as of June 30, 2017	311,422		$	3.56	6.94	$	593,984
Exercisable as of June 30, 2017	21,616		$	2.91	5.73	$	291,021

Summary of restricted stock unit and stock award activity

The following table summarizes the restricted stock unit, including PRSUs, activity under our share-based plans for the six months ended June 30, 2017:



	Shares		Grant Date Fair Value Per Share
Nonvested as of December 31, 2016	29,893		$	4.03
Granted	1,660		$	4.52
Vested	(978	)	$	3.83
Forfeited	(490	)	$	4.09
Nonvested as of June 30, 2017	30,085		$	4.07