60% is the turning point of pretty much no return in being an attractive school to prospective students. But to keep from hitting that dread point they accept boys with lesser records than girls.
You need to follow it a little more closely.
I dispute the contention that boys are less qualified; I’ve seen the gender breakdown in higher-level classes, and many of the replacement Americans’ cultures wouldn’t even bother sending a female to college (they’re the ones reproducing). Now they just want to move that 59% up to the graduate and doctorate level, since there really is no shortage of American males that can make the cut.