Note 6. Accounting for Stock-Based Compensation

6 Months Ended

Jun. 30, 2016

Notes to Financial Statements

Disclosure of Compensation Related Costs, Share-based Payments [Text Block]

6.

Accounting for Stock-Based Compensation

During the three month periods ended June 30, 2016 and 2015, the Company granted 24,000 and 27,000, respectively, of stock options to employees or directors. The Company recognized $20,000 and $44,000, respectively, of stock-based compensation expense for the three month periods ended June 30, 2016 and 2015. During the six month periods ended June 30, 2016 and 2015, the Company granted 24,000 and 40,000, respectively, of stock options to employees and directors. The Company recognized $62,000 and $112,000, respectively, of stock-based compensation expense for the six month periods ended June 30, 2016 and 2015.

During the three month periods ended June 30, 2016 and 2015, no options were exercised under the 2005 Plan, respectively. During the six month periods ended June 30, 2016 and 2015, 136,000 and 150,000 were exercised under the 2005 Plan, respectively.

Valuation Assumptions

The fair values of employee and director option awards were estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions:

	For Three Months Ended June 30, 2016			For Three Months Ended June 30, 2015			For Six Months Ended June 30, 2016			For Six Months Ended June 30, 2015
Weighted average grant date fair value	$	0.29		$	1.93		$	0.29		$	2.11
Weighted average assumptions used:
Expected dividend yield		0.0	%		0.0	%		0.0	%		0.0	%
Risk-free interest rate		1.38	%		1.33	%		1.38	%		1.38	%
Expected volatility		96.0	%		170.0	%		96.0	%		176.3	%
Expected life (in years)		5.0			5.0			5.0			5.0

Expected volatility is based on historical volatility and in part on implied volatility. The expected term considers the contractual term of the option as well as historical exercise and forfeiture behavior. The risk-free interest rate is based on the rates in effect on the grant date for U.S. Treasury instruments with maturities matching the relevant expected term of the award. Options granted to non-employees are valued using the fair market value on each measurement date of the option.