edwards lifesciences corporation notes to consolidated financial statements ( continued ) 12 . employee benefit plans ( continued ) equity and debt securities are valued at fair value based on quoted market prices reported on the active markets on which the individual securities are traded . the insurance contracts are valued at the cash surrender value of the contracts , which is deemed to approximate its fair value . the following benefit payments , which reflect expected future service , as appropriate , at december 31 , 2016 , are expected to be paid ( in millions ) : .
what is the percent change of benefits expected to be paid between 2017 and 2018?
as of december 31 , 2016 , expected employer contributions for 2017 are $ 6.1 million . defined contribution plans the company 2019s employees in the united states and puerto rico are eligible to participate in a qualified defined contribution plan . in the united states , participants may contribute up to 25% ( 25 % ) of their eligible compensation ( subject to tax code limitation ) to the plan . edwards lifesciences matches the first 3% ( 3 % ) of the participant 2019s annual eligible compensation contributed to the plan on a dollar-for-dollar basis . edwards lifesciences matches the next 2% ( 2 % ) of the participant 2019s annual eligible compensation to the plan on a 50% ( 50 % ) basis . in puerto rico , participants may contribute up to 25% ( 25 % ) of their annual compensation ( subject to tax code limitation ) to the plan . edwards lifesciences matches the first 4% ( 4 % ) of participant 2019s annual eligible compensation contributed to the plan on a 50% ( 50 % ) basis . the company also provides a 2% ( 2 % ) profit sharing contribution calculated on eligible earnings for each employee . matching contributions relating to edwards lifesciences employees were $ 17.3 million , $ 15.3 million , and $ 12.8 million in 2016 , 2015 , and 2014 , respectively . the company also has nonqualified deferred compensation plans for a select group of employees . the plans provide eligible participants the opportunity to defer eligible compensation to future dates specified by the participant with a return based on investment alternatives selected by the participant . the amount accrued under these nonqualified plans was $ 46.7 million and $ 35.5 million at december 31 , 2016 and 2015 , respectively . 13 . common stock treasury stock in july 2014 , the board of directors approved a stock repurchase program authorizing the company to purchase up to $ 750.0 million of the company 2019s common stock . in november 2016 , the board of directors approved a new stock repurchase program providing for an additional $ 1.0 billion of repurchases of our common stock . the repurchase programs do not have an expiration date . stock repurchased under these programs may be used to offset obligations under the company 2019s employee stock-based benefit programs and stock-based business acquisitions , and will reduce the total shares outstanding . during 2016 , 2015 , and 2014 , the company repurchased 7.3 million , 2.6 million , and 4.4 million shares , respectively , at an aggregate cost of $ 662.3 million , $ 280.1 million , and $ 300.9 million , respectively , including .