12. EQUITY

Common Stock

The Company has paid quarterly dividends on its common stock since January 1999.

Treasury Stock

During the years ended December 31, 2013, 2014 and 2015, the Company repurchased the following shares from employees to satisfy tax withholding and stock options exercise obligations incurred in connection with the vesting of restricted stock awards and the exercise of stock options:


		Aggregate
	Shares	Cost		Average
Year ended December 31,	Repurchased	(in thousands)		Repurchase Price
2013	163,222	$	8,103	$	49.64
2014	34,293		2,160		63.01
2015	37,567		2,705		72.01

Stock‑Based Compensation

The Company has 2,000,000 shares reserved for the grant of stock options, restricted stock, restricted stock units, stock equivalents and awards of shares of common stock that are not subject to restrictions or forfeiture.

Stock Options

Stock options have a term of ten years and vest annually and ratably over a period of four years.

The following table summarizes stock option activity for the years ended December 31, 2014 and 2015:


	Year Ended December 31, 2014
				Weighted Average
				Remaining
	Number of	Weighted Avg.		Contractual	Aggregate
	Options	Exercise Price		Term (Years)	Intrinsic Value
Outstanding at January 1, 2014	401,287	$	36.63
Exercised	(43,034)		37.68
Forfeited—Unvested	(7,000)		34.22
Outstanding at December 31, 2014	351,253		36.55	5.0	$	10,901,529
Vested and expected to vest at December 31, 2014	351,142		36.56	5.0	$	10,987,590
Exercisable at December 31, 2014	290,128		36.81	4.6	$	8,929,815


	Year Ended December 31, 2015
				Weighted Average
		Weighted Avg.		Remaining
	Number of	Exercise		Contractual	Aggregate
	Options	Price		Term (Years)	Intrinsic Value
Outstanding at January 1, 2015	351,253	$	36.55
Granted	5,000		71.43
Exercised	(87,378)		32.14
Forfeited—Unvested	—		—
Outstanding at December 31, 2015	268,875		38.64	4.7	$	10,646,006
Vested and expected to vest at December 31, 2015	268,011		38.53	4.7	$	10,640,134
Exercisable at December 31, 2015	248,875		38.05	4.5	$	9,998,956

The unvested options as of December 31, 2015 represent $0.2 million in unamortized stock‑based compensation which will be recognized over a weighted average term of 2.61 years.

The following table summarizes information relating to options granted and exercised during the years ended December 31, 2013, 2014 and 2015 (in thousands, except fair value of options granted data):


	2013		2014		2015
Weighted-average fair value of options granted	$	N/A	$	N/A	$	30.70
Aggregate intrinsic value of options exercised		6,111		1,098		3,488
Cash proceeds received upon exercise of options		2,669		1,621		1,999
Excess tax benefits from share-based compensation		2,101		513		1,423

The aggregate intrinsic value represents the total pre‑tax intrinsic value (the difference between our closing common stock price on December 31st and the exercise price, multiplied by the number of the in‑the‑money stock options) that would have been received by the stock option holders had all stock options holders exercised their stock options on December 31st. The amount of aggregate intrinsic value will change based on the fair market value of our common stock.

The Company did not grant any options during 2013 or 2014. The estimated fair value of the options granted during 2015 were determined using a Black Scholes option pricing model, based on the following weighted average assumptions:


	Options Granted in
	2015
Risk-free interest rate	1.55	%
Expected dividend yield	1.76	%
Expected life	6.25	years
Expected volatility	51.85	%

The Company recognized $1.4 million, $0.9 million and $0.4 million, respectively, of stock compensation expense relating to the granted options during 2013, 2014 and 2015, respectively.

Restricted Stock

Restricted stock issued under the 2008 Equity Investment Plan vest ratably over four years.

The following table summarizes restricted stock activity during the year ended December 31, 2014:


		Weighted Avg.
	Shares	Fair Value
Unvested as of January 1, 2014	154,519	$	44.04
Granted	109,318		64.73
Forfeited	(8,500)		51.44
Vested and issued	(60,194)		44.61
Unvested as of December 31, 2014	195,143	$	55.13

The following table summarizes restricted stock activity during the year ended December 31, 2015:


		Weighted Avg.
	Shares	Fair Value
Unvested as of January 1, 2015	195,143	$	55.13
Granted	93,864		66.26
Forfeited	(1,687)		65.18
Vested and issued	(68,919)		52.70
Unvested as of December 31, 2015	218,401	$	60.60

In connection with the grant of restricted shares, the Company recognized $3.1 million, $3.4 million and $4.3 million of compensation expense within its income statements for the years ended December 31, 2013, 2014 and 2015, respectively.

The unvested shares as of December 31, 2015 represent $9.4 million in unamortized stock based compensation which will be recognized over a weighted average period of 2.6 years.