LONDON: Novak Djokovic completed the best year of his career and one of the best by any player in the professional era when the Serb beat Roger Federer to win the ATP World Tour Finals on Sunday.

Here are the important numbers from the past 12 months:

Titles: 11

Grand slam titles: 3. Australian Open (beat Andy Murray), Wimbledon (beat Federer), US Open (beat Federer)

Masters Series titles: 6. Indian Wells, Miami, Monte Carlo, Rome, Shanghai, Paris.Became the first player to win the Indian Wells/Miami double three times.

ATP World Tour Finals: Beats Federer to become first player to win the season-ender four years in a row.

Match win/loss record: 82-6 (first player to win 80 matches in a season since Rafael Nadal (82-11) in 2008

Has been ranked No.1 by the ATP since July, 2014.

First player to top the rankings every week of the year since Federer in 2007

Since losing to Ivo Karlovic in the quarter-finals in Doha at the start of the year, Djokovic has reached the final of every tournament he has played in, 15 in all.

First player to reach all four grand slam finals in a season since Federer in 2009.

Percentage of service games won in 2015: 90

Prize money this year: $18.767 million