Why did Yale's academic reputation score plunge from (tied for) 3rd to (tied for) 6th this year?

Was it because Yale led the charge on the boycott of USNews.com?  Was it the accumulated effect of various embarrassing events, from judges boycotting Yale over free expression issues to the Amy Chua melodrama?  Was it a reflection of a widely perceived decline in the strength of Yale's younger faculty compared to their elders?   Was it all of these?  What's clear is the drop this year was pretty dramatic by historical standards for USNews.com reputation surveys, and of course this year is way down from a decade or so ago when Yale was usually tied for 1st or 2nd in academic reputation.