shareholder value award program svas are granted to officers and management and are payable in shares of our common stock . the number of shares actually issued , if any , varies depending on our stock price at the end of the three-year vesting period compared to pre-established target stock prices . we measure the fair value of the sva unit on the grant date using a monte carlo simulation model . the model utilizes multiple input variables that determine the probability of satisfying the market condition stipulated in the award grant and calculates the fair value of the award . expected volatilities utilized in the model are based on implied volatilities from traded options on our stock , historical volatility of our stock price , and other factors . similarly , the dividend yield is based on historical experience and our estimate of future dividend yields . the risk-free interest rate is derived from the u.s . treasury yield curve in effect at the time of grant . the weighted-average fair values of the sva units granted during the years ended december 31 , 2018 , 2017 , and 2016 were $ 48.51 , $ 66.25 , and $ 48.68 , respectively , determined using the following assumptions: .

2018: expected dividend yield: -2.5
risk-free interest rate: 2.31
volatility: 22.26
2017: expected dividend yield: -2.5
risk-free interest rate: 1.38
volatility: 22.91
2016: expected dividend yield: -2
risk-free interest rate: 0.92
volatility: 21.68

pursuant to this program , approximately 0.7 million shares , 1.1 million shares , and 1.0 million shares were issued during the years ended december 31 , 2018 , 2017 , and 2016 , respectively . approximately 1.0 million shares are expected to be issued in 2019 . as of december 31 , 2018 , the total remaining unrecognized compensation cost related to nonvested svas was $ 55.7 million , which will be amortized over the weighted-average remaining requisite service period of 20 months . restricted stock units rsus are granted to certain employees and are payable in shares of our common stock . rsu shares are accounted for at fair value based upon the closing stock price on the date of grant . the corresponding expense is amortized over the vesting period , typically three years . the fair values of rsu awards granted during the years ended december 31 , 2018 , 2017 , and 2016 were $ 70.95 , $ 72.47 , and $ 71.46 , respectively . the number of shares ultimately issued for the rsu program remains constant with the exception of forfeitures . pursuant to this program , 1.3 million , 1.4 million , and 1.3 million shares were granted and approximately 1.0 million , 0.9 million , and 0.6 million shares were issued during the years ended december 31 , 2018 , 2017 , and 2016 , respectively . approximately 0.8 million shares are expected to be issued in 2019 . as of december 31 , 2018 , the total remaining unrecognized compensation cost related to nonvested rsus was $ 112.2 million , which will be amortized over the weighted- average remaining requisite service period of 21 months . note 12 : shareholders' equity during 2018 , 2017 , and 2016 , we repurchased $ 4.15 billion , $ 359.8 million and $ 540.1 million , respectively , of shares associated with our share repurchase programs . a payment of $ 60.0 million was made in 2016 for shares repurchased in 2017 . during 2018 , we repurchased $ 2.05 billion of shares , which completed the $ 5.00 billion share repurchase program announced in october 2013 and our board authorized an $ 8.00 billion share repurchase program . there were $ 2.10 billion repurchased under the $ 8.00 billion program in 2018 . as of december 31 , 2018 , there were $ 5.90 billion of shares remaining under the 2018 program . we have 5.0 million authorized shares of preferred stock . as of december 31 , 2018 and 2017 , no preferred stock was issued . we have an employee benefit trust that held 50.0 million shares of our common stock at both december 31 , 2018 and 2017 , to provide a source of funds to assist us in meeting our obligations under various employee benefit plans . the cost basis of the shares held in the trust was $ 3.01 billion at both december 31 , 2018 and 2017 , and is shown as a reduction of shareholders 2019 equity . any dividend transactions between us and the trust are eliminated . stock held by the trust is not considered outstanding in the computation of eps . the assets of the trust were not used to fund any of our obligations under these employee benefit plans during the years ended december 31 , 2018 , 2017 , and .

Questions:
what was the volatility in 2017?
and what was it in 2016?
what was, then, the change over the year?
and how much does this change represent in relation to the 2016 volatility, in percentage?

Answers:
22.91
21.68
0.23
1.1%