2014 2013 2012 Weighted-average per share grant-date fair value Stock options N/A $ 7.46 $ 7.88 SARs N/A 7.45 7.84 Intrinsic value of awards exercised or vested Stock options / SARs $ 7 $ 14 $ 18 RSUs / PSUs 8 5 11 Options SARs 2013 2012 2013 2012 Expected term (in years) 6.00 6.00 6.00 6.00 Risk-free interest rate 1.07% 1.24% 1.07% 1.24% Dividend yield 1.41% 1.33% 1.41% 1.33% Expected volatility 55.80% 59.90% 55.80% 59.90% Compensation expense is generally measured based on the fair value at the date of grant and is recognized on a straight- line basis over the vesting period. For options and SARs, we use an option-pricing model to estimate fair value. For RSUs and  PSUs, the fair value is based on the closing market price of our common stock at the date of grant.  Awards that are settled in  cash are subject to liability accounting. Accordingly, the fair value of such awards is remeasured at the end of each reporting  period until settled or expired. We had accrued $6 and $5 for cash-settled awards at December 31, 2014 and 2013. We recognized total stock compensation expense of  $16, $16 and $19 during 2014, 2013 and 2012. The total fair value of  awards vested during 2014, 2013 and 2012 was $13, $10 and $18. We received $7, $15 and $10 of cash from the exercise of  stock options and we paid $2, $4 and $2 of cash to settle SARs, RSUs and PSUs during  2014, 2013 and 2012. We issued 0.3  million in RSUs in 2014 based on vesting. At December 31, 2014, the total unrecognized compensation cost related to the  nonvested awards granted and expected to vest was  $20. This cost is expected to be recognized over a weighted-average period  of 1.8 years. Stock options and stock appreciation rights  — The exercise price of each option or SAR equals the closing market price of our  common stock on the date of grant. Options and SARs generally vest over  three years and their maximum term is ten years.  Shares issued upon the exercise of options are recorded as common stock and additional paid-in capital at the option price.  SARs are settled in cash for the dif ference between the market price on the date of exercise and the exercise price. We estimated fair values for options and SARs at the date of grant using the following key assumptions as part of the  Black-Scholes option pricing model. The expected term was estimated using the simplified method because the limited period  of time our common stock had been publicly traded provided insuf ficient historical exercise data. The risk-free rate was based  on U.S. Treasury security yields at the time of grant.  The dividend yield was calculated by dividing the expected annual  dividend by the average stock price of our common stock over the prior year . The expected volatility was estimated using a  combination of the historical volatility of similar entities and the implied volatility of our exchange-traded options. Restricted stock units and performance shares units  — Each RSU or PSU granted represents the right to receive one share of  Dana common stock or, at the election of Dana (for units awarded to board members) or for employees located outside the U.S.  (for employee awarded units), cash equal to the market value per share.  All RSUs contain dividend equivalent rights. RSUs  granted to non-employee directors vest on the first anniversary date of the grant and those granted to employees generally clif f  vest fully after three years. PSUs granted to employees are awarded if specified performance goals are achieved during the  respective performance period. The number of PSUs that ultimately vest is contingent on achieving specified return on invested capital tar gets and  specified total shareholder return tar gets relative to peer companies. For the portion of the award based on the return on  invested capital performance metric, we estimated the fair value of the PSUs at grant date based on the closing market price of  our common stock at the date of grant adjusted for the value of assumed dividends over the period because the award is not  dividend protected. For the portion of the award based on shareholder returns, we estimated the fair value of the PSUs at grant  date using various assumptions as part of a Monte Carlo simulation.  The expected term represents the period from the grant  date to the end of the three-year performance period. The risk-free interest rate of  0.64% was based on U.S. Treasury constant  maturity rates at the grant date.  The dividend yield of 1.02% was calculated by dividing the expected annual dividend by the  average stock price over the prior year. The expected volatility of 43.6% was based on historical volatility over the prior three  years using daily stock price observations. 60