Complex sentence: She has been ranked in FIDE's top 50 highest rated female chess players in the world during the early 2000s, with her best ranking being the 40th highest rated female chess player in the world in January 2003, with a rating of 2415.
Split into simpler sentences: She has been ranked in FIDE's top 50 highest rated female chess players in the world during the early 2000s. Her best ranking is the 40th highest rated female chess player in the world in January 2003, with a rating of 2415.