perches

ここのperchは面白いですね。perchはbarという意味のラテンだったと思いますが、このような用法は知りませんでした。「上位の座」、"informal a high place or position, especially one where you can sit and watch something" （OALD）という意味です。「指定席」「牙城」などという言葉も連想しました。（UG）

College rankings reflect change in emphasis

Penn State University and a pair of small liberal arts colleges in California made some of the biggest gains this year in the U.S. News & World Report annual rankings.

None of them pushed perennially top-ranked schools such as Princeton or Williams out of their top perches, but they fared well under a revised formula that puts less emphasis on who gets admitted and more on whether students graduate.

The changes "take into account the latest data and trends in higher education," said Robert Morse, U.S. News director of data research. They have been in the works since early this summer, he added, weeks before President Obama announced plans for the Education Department to develop a "new rating system" that analyzes a school's success in graduating low-income students and preparing them for jobs.

http://www.usatoday.com/story/news/nation/2013/09/09/us-news-college-rankings-universities/2791069/