contributions and expected benefit payments the funding of our qualified defined benefit pension plans is determined in accordance with erisa , as amended by the ppa , and in a manner consistent with cas and internal revenue code rules . in 2015 , we made $ 5 million in contributions to our new sikorsky bargained qualified defined benefit pension plan and we plan to make approximately $ 25 million in contributions to this plan in 2016 . the following table presents estimated future benefit payments , which reflect expected future employee service , as of december 31 , 2015 ( in millions ) : .
what is the change in millions of qualified defined benefit pension plans expected to be paid out between 2017 to 2018?
defined contribution plans we maintain a number of defined contribution plans , most with 401 ( k ) features , that cover substantially all of our employees . under the provisions of our 401 ( k ) plans , we match most employees 2019 eligible contributions at rates specified in the plan documents . our contributions were $ 393 million in 2015 , $ 385 million in 2014 and $ 383 million in 2013 , the majority of which were funded in our common stock . our defined contribution plans held approximately 40.0 million and 41.7 million shares of our common stock as of december 31 , 2015 and 2014 . note 12 2013 stockholders 2019 equity at december 31 , 2015 and 2014 , our authorized capital was composed of 1.5 billion shares of common stock and 50 million shares of series preferred stock . of the 305 million shares of common stock issued and outstanding as of december 31 , 2015 , 303 million shares were considered outstanding for balance sheet presentation purposes ; the remaining shares were held in a separate trust . of the 316 million shares of common stock issued and outstanding as of december 31 , 2014 , 314 million shares were considered outstanding for balance sheet presentation purposes ; the remaining shares were held in a separate trust . no shares of preferred stock were issued and outstanding at december 31 , 2015 or 2014 . repurchases of common stock during 2015 , we repurchased 15.2 million shares of our common stock for $ 3.1 billion . during 2014 and 2013 , we paid $ 1.9 billion and $ 1.8 billion to repurchase 11.5 million and 16.2 million shares of our common stock . on september 24 , 2015 , our board of directors approved a $ 3.0 billion increase to our share repurchase program . inclusive of this increase , the total remaining authorization for future common share repurchases under our program was $ 3.6 billion as of december 31 , 2015 . as we repurchase our common shares , we reduce common stock for the $ 1 of par value of the shares repurchased , with the excess purchase price over par value recorded as a reduction of additional paid-in capital . due to the volume of repurchases made under our share repurchase program , additional paid-in capital was reduced to zero , with the remainder of the excess purchase price over par value of $ 2.4 billion and $ 1.1 billion recorded as a reduction of retained earnings in 2015 and 2014 . we paid dividends totaling $ 1.9 billion ( $ 6.15 per share ) in 2015 , $ 1.8 billion ( $ 5.49 per share ) in 2014 and $ 1.5 billion ( $ 4.78 per share ) in 2013 . we have increased our quarterly dividend rate in each of the last three years , including a 10% ( 10 % ) increase in the quarterly dividend rate in the fourth quarter of 2015 . we declared quarterly dividends of $ 1.50 per share during each of the first three quarters of 2015 and $ 1.65 per share during the fourth quarter of 2015 ; $ 1.33 per share during each of the first three quarters of 2014 and $ 1.50 per share during the fourth quarter of 2014 ; and $ 1.15 per share during each of the first three quarters of 2013 and $ 1.33 per share during the fourth quarter of 2013. .