May I suggest you haven't looked very hard?
Here's a NYT article asking whether Princeton is anti-Semitic because (in 1999) its Jewish enrollment had dropped to about 10%, still at least 5x their percentage of the population.
http://www.nytimes.com/1999/06/02/nyregion/princeton-puzzle-where-have-jewish-students-gone.html
This is as compared with the other Ivies, which are commended in the article for maintaining 1/4, 1/3 or higher numbers. (My understanding is that Princeton has since addressed this "problem.")
My question is this. Assuming people who think this way aren't idiots, aren't they aware that bringing "under-represented minorities" up to their appropriate representation, while at the same time recruiting 1/4 or 1/3 Jews is exactly the same thing as imposing a 25% cap on white gentile enrollment? Which is, of course, exactly what was done to Jews in the early 20th, except of course being far more savage.
During the quota period at Harvard, for example, Jewish enrollment never dropped below 15%, still far above their percentage of the population at the time. The effective quotas at Harvard today cap white gentiles at probably considerably less than half their percentage of the population. And nobody cares.
My estimate is that the [Jewish] "quota period at Harvard" lasted roughly from the 1920s (when noted alum Franklin D. Roosevelt played a key role in instituting it) until sometime in the 1960s. My guess would be that Jewish enrollment at Harvard was below 15% during the earlier parts of that period, although I have no statistics in front of me at present. There was one particular Harvard president, whose name escapes me, who was notorious in lowering Jewish admissions numbers.
When you consider Jewish student enrollment in the Ivies, you have to take geography into account as well, in that the Ivies are located in the Northeast and draw most of their students from that section in the country. The Jewish population comprises - although to a lesser degree than it did back in previous decades - a significantly higher percentage of the population in the Northeast than it does nationally. So giving the national Jewish percentage of the population as a baseline is a bit of a distortion in this discussion. Most Jewish youngsters from other sections of the US never were interested in the Ivies and instead chose schools in their region. (Also the Jewish population nationally was more like 4% in in the 1930s and 1940s, and has now gradually diminished to 2% due to low birth rates, assimilation, and relatively small immigration rates.)
My intuitive take, overall, is that the current Jewish student population, though still represented in elite schools far out of proportion to its percentage in the population, has not statistically performed as remarkably well as its parents and grandparents generations of Jewish students. Asian students now seem to be accounting for even higher percentages of elite college admissions when compared to their percentages in the population than Jewish students are.