The Company’s 2015 Equity Incentive Plan (the “Plan”) was adopted by the Company and approved by its shareholders in April 2015. The maximum number of shares of common stock that may be issued pursuant to stock-based awards under the Plan equals 1,100,000 shares, all of which may be subject to incentive stock option treatment. Option awards are generally granted with an exercise price equal to the market price of the Company’s common stock at the date of grant; those option awards have vesting periods ranging from 5 to 10 years and have 10-year contractual terms. Restricted stock awards vest under the period of restriction specified within their respective award agreements as determined by the Company. Forfeitures are recognized as they occur, subject to a 90-day grace period for vested options.

The fair value of each option award is estimated on the date of grant using a closed form option valuation (Black-Scholes) model that uses the assumptions noted in the table below. Expected volatilities are based on historical volatilities of the Company’s common stock and similar peer group averages. The Company uses historical data to estimate option exercise and post-vesting termination behavior. The expected term of options granted is based on historical data and represents the period of time that options granted are expected to be outstanding, which takes in to account that the options are not transferable. The risk-free interest rate for the expected term of the option is based on U.S. Treasury yield curve in effect at the time of the grant.

A summary of stock option activity in the Plan during the three months ended March 31, 2021 and 2020 follows:

Three Months Ended March 31, 2021	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life in Years		Aggregate Intrinsic Value
Outstanding at beginning of year		506,200		$	26.81		5.82	$	1,805
Effect of 10% stock dividend		50,770
Granted		24,500			33.37		9.86		83
Exercised		(24,250	)		21.74		3.28		364
Forfeited		(10,000	)		28.54		5.97		82
Balance, March 31, 2021		547,220		$	24.81		5.88	$	6,532

Exercisable at end of period		296,922		$	23.49		4.64	$	3,938

Three Months Ended March 31, 2020	Number of Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life in Years		Aggregate Intrinsic Value
Outstanding at beginning of year		508,000		$	26.68		6.24	$	3,159
Granted		23,000			29.00		9.84		11
Exercised		(3,000	)		24.00		2.54		—
Forfeited		(24,400	)		31.72		8.46		—
Balance, March 31, 2020		503,600		$	26.55		6.07	$	21

Exercisable at end of period		260,880		$	25.26		5.01	$	7

A summary of nonvested stock option activity in the Plan during the three months ended March 31, 2021 and 2020 follows:

Three Months Ended March 31, 2021	Number of Shares			Weighted-Average Grant Date Fair Value
Outstanding at beginning of year		214,680		$	4.46
Effect of 10% stock dividend		23,218
Granted		24,500			5.67
Vested		(12,100	)		(4.59	)
Forfeited		—			—
Balance, March 31, 2021		250,298		$	5.11

Three Months Ended March 31, 2020	Number of Shares			Weighted-Average Grant Date Fair Value
Outstanding at beginning of year		251,120		$	4.97
Granted		23,000			5.62
Vested		(8,200	)		(5.18	)
Forfeited		(23,200	)		(1.93	)
Balance, March 31, 2020		242,720		$	5.90

Information related to stock options in the Plan is as follows for the three months ended:

	March 31, 2021		March 31, 2020
Intrinsic value of options exercised	$	364	$	—
Cash received from options exercised		527		72
Weighted average fair value of options granted		5.67		5.62

A summary of restricted stock activity in the Plan during the three months ended March 31, 2021 and 2020 follows:

Three Months Ended March 31, 2021	Number of Shares			Weighted-Average Grant Date Fair Value
Outstanding at beginning of year		35,300		$	29.72
Effect of 10% stock dividend		3,530			—
Granted		—			—
Vested		(4,840	)		30.25
Forfeited		—			—
Balance, March 31, 2021		33,990		$	26.95

Three Months Ended March 31, 2020	Number of Shares			Weighted-Average Grant Date Fair Value
Outstanding at beginning of year		31,459		$	30.29
Granted		—			—
Vested		(6,100	)		30.25
Forfeited		—			—
Balance, March 31, 2020		25,359		$	30.29

Restricted stock granted to employees typically vests over five years, but vesting periods may vary. Compensation expense for these grants will be recognized over the vesting period of the awards based on the fair value of the stock at the issue date.

As of March 31, 2021, there was $2,128 of total unrecognized compensation expense related to unvested stock options granted and restricted stock granted under the Plan. The expense is expected to be recognized over a weighted-average period of 3.30 years.

The Company granted options under the Plan during the first three months of 2021 and 2020. Expense of $162 was recorded during both the three months ended March 31, 2021 and 2020, which represents the stock options and fair value of shares vested during those periods.