One measurement that selective colleges use to compare themselves is their respective admissions yields: the percentage of applicants offered acceptance who ultimately decide to enroll, The New York Times reports. A few institutions — including Harvard, Dartmouth, Cornell and the University of North Carolina at Chapel Hill — have begun to report those figures for the freshman class that will take its seats next fall, and so far none have experienced any downturn in the midst of the sluggish economy. At Harvard, for example, more than three of every four applicants who received an acceptance letter had committed by the May 1 deadline to enroll, a slight increase over last year. (The university said it still expected to offer acceptance to as many as 75 applicants on its waiting list.) At Dartmouth, the yield for the new freshman class was 55 percent, an increase of seven percentage points; the increase was so large that the college said it might not have room for anyone on its waiting list.