.79"], ["vested", "-858 ( 858 )", "39.26"], ["forfeited", "-78 ( 78 )", "59.56"], ["unvested at december 31 2017", "1226", "78.29"], ["granted", "650", "109.85"], ["vested", "-722 ( 722 )", "60.08"], ["forfeited", "-70 ( 70 )", "91.47"], ["unvested at december 31 2018", "1084", "$ 108.51"]]