LOS ANGELES (Reuters) - Tiger Woods plummeted depths he has not reached in 14 years when he dropped four spots to 12th in the world rankings issued on Monday. The former world number one has not triumphed anywhere since the 2009 Australian Masters and has been steadily losing ranking points because of his recent struggles on and off the course. In Monday's rankings, Woods is sandwiched by fellow Americans Bubba Watson (in 11th) and Dustin Johnson (13th), the first time he has been out of the top 10 since he was 13th on April 6, 1997.