One year ago , the Swiss star made his 100th career final at the ATP World Tour Finals , winning his 70th career title .
It marks the 8th final for Federer in his 11 appearances at the season - ending championships .
One year ago , the Swiss Federer made Federer 's 100th career final at the ATP World Tour Finals , winning his 70th career title .
It marks the 8th final for Federer in his 11 appearances at the season - ending championships .