<p>JHS:</p>
<p>I don't have the Yale numbers handy, although they are available in the on-line Yale factbook.</p>
<p>Swarthmore's acceptance rate was 23% in 1970 and 22% in 2005.</p>
<p>Williams acceptance rate was 19% in 1980 and 19% in 2005. </p>
<p>The general trend was low acceptance rates during the baby-boom. A steady increase in acceptance rates from the 1970s through the mid-1990s -- there were simply fewer college age people in the pipeline. Followed by a decline in acceptance rates over the last ten years as the echo-boom demographic bulge moves through the system.</p>
<p>The details of the intervening years vary from school to school. For example, most of the male schools in the northeast were able to partially offset the declining college population by doubling their applicant pools with the admission of women.</p>
<p>The historically co-ed schools got a double-whammy in the 1970s -- the end of the baby boom bulge and newfound coed competion from the Ivies and other elite colleges. For example, in 1965, it could be legitimately argued that Swarthmore was the most prestigious coed school in the northeast. Ten years or so later, Harvard, Yale, Princeton, Columbia, Dartmouth, Brown, Williams, Amherst, Duke, UVa and many more were coed institutions accepting applications from women. The impact of that is easy to see in Swarthmore's acceptance rates for a decade or so starting from the mid 1970s to the mid 1980s. They jumped from a 23% acceptance rate in 1970 to 40% in 1975. Colleges that went coed were seeing the opposite effect, although not enough to completely offset the end of the baby boom bulge. It appears that the one-time statistical disruption from the co-ed movement appears to have stabilized by 1990 or so.</p>
<p>As for median SAT scores, don't forget that the SATs were recentered for the entering class in the fall of 1995. In their Institution Research data, Swarthmore reports the median scores for the fall 1995 freshmen both ways -- original formula and recentered.</p>
<p>For the same cohort of freshmen, the middle 50% were:</p>
<p>Old-style: 1260-1440
Recentered: 1320-1500</p>
<p>From the years 1970 up through the recentering for 1995, there had been little change: a 20 point drop in median verbal and a 20 point rise in median math.</p>
<p>Since the recentering in 1995, there has been a slight increase: 20 points in Verbal, 20 points in Math. That rise corresponds to the increased number of echo-boom applications (and perhaps to the increased emphasis on test-prep, multiple sittings, etc.).</p>
<p>The way I read the data: college admissions are mostly a function of the allocation of slots (male/female, white/non-white) and the ebb and flow of demographics in the underlying population. Looking to the future, the trend colleges see is a decline in white high school seniors from the northeast corriodor and a rapid increase in Latino and Asian American applicants from other regions. I think that colleges making big diversity pushes today are doing so, in part, to position themselves for the demographics of the future just as colleges decided to admit women when they were staring at a significant decline in their previous applicant pools.</p>