Since the ATP computerized ranking was introduced in 1973, 100 players have spent at least one week inside the ATP Top 50. The all-time leader is Roger Federer with 1133 weeks, a margin 12% ahead of Novak Djokovic (1015 weeks) and Rafael Nadal (996 weeks). 100 players have accumulated 52 or more weeks inside the Top 50, with an average of 578 weeks across all ranked players.