Disparity between world's highest paid female athlete and male athlete

Maria Sharapova is the World's highest paid female athlete. Her annual income for 2013 is $29 Mn. However she is still miles away from the World's highest paid male athlete - Tiger Woods. He earns $78 Mn this year. What a disparity between male and female earnings, even at that top level. Anyways, Congrats Maria Sharapova. Keep it up.