.7 to 1.0 at year-end 2018 . see the 201ccash requirements and our credit facility , 201d caption in this 201cliquidity and capital resources 201d section for more information on our credit facility . share repurchases . we purchased 21.5 million shares of our common stock in 2018 at an average price of $ 130.67 per share , 29.2 million shares in 2017 at an average price of $ 103.66 per share , and 8.0 million shares in 2016 at an average price of $ 71.55 per share . at year-end 2018 , 10