Well because Clijsters still hasn't 16 tournaments played, so everytime she win points they are counted all. But Yanina has still more tournaments played, so the points of winning this event replace the points of an other tournament.
So Kim recieved 260 more, Yanina not because she had for example 70 points from an other tournament, so 260-70, she recieves 190 points more than last week. (the points are just a guess, it aren't the exact points)
But i hope that you understand what i mean. Btw the ranking of a player is based on 16 tournaments, 8 mandotory and 8 of her best results