LONDON, JUNE 2: Steffi Graf, who has spent more time as the No 1-ranked woman than anybody else, will drop out of the WTA tour rankings on Monday.Graf, the winner of 21 Grand Slam singles title, has played only two tournaments since she was beaten last year at the French Open. A player must play at least three tournaments in a year to stay ranked.The German, No 60 in the latest WTA weekly rankings, held No 1 for 374 weeks, topping No 2 Martina Navratilova at 331. Graf, who will be 29 later this month, last held the No 1 spot on March 30, 1997.Graf's recent comeback attempt has faltered since undergoing surgery on her left knee.