UPDATE: The fraction of the class filled from SCEA pool at Harvard and Yale:

<li><p>Yale accepted 710 EA this year. If they all enroll, that will constitute 54% of the class - if it meets the targeted 1,310 figure after summer melt and without resort to the waitlist.</p></li>
<li><p>Harvard accepted 885 EA this year. If they all enroll, that will constitute precisely the same 54% of the class - assuming it matches last year’s 1,638 total without resort to the waitlist.</p></li>
<li><p>Last year, of course, 91% of Harvard’s EA admits enrolled, while 88% of Yales EA admits enrolled.</p></li>
<li><p>Keep the following tidbit in mind, however: last year, Harvard accepted an estimated 139 of 2,788 EA deferreds (an admit rate of 4.9%), while Yale accepted 249 from its much smaller group of EA deferreds (an admit rate of about 14%, vs a much lower admit rate for “ordinary” RD applicants at Yale.). Doubtless, these EA deferreds can be counted on to enroll at a higher rate than “normal” RD applicants at each school.</p></li>
<li><p>So arguably, at the end of the day, Harvard admitted enough EA pool applicants to fill 63% of the class last year - if they all had enrolled - and Yale admitted enough from this loyal applicant pool to fill a whopping 70% of the class of 2008 - again, if they all had enrolled!</p></li>
<li><p>Now, without considering this “hidden” group of anxious and willing EA deferreds to be “EA admits”, what fraction of the respective classes at Harvard and Yale will be filled from the EA pool for the Class of 2009? Assuming last year’s SCEA yield rates hold, 49% of Harvard matriculants will have been EA admits, while about the same 49% of Yale matriculants will have been SCEA admits.</p></li>
</ol>

<p>Obviously, both are striving to admit as many from the EA pool as possible, while staying under the “magic” 50% line</p>

<p>Cool info! Thanks Byerly.... sheesh, 49% is a ton!</p>

<p>why is there this 49% line? What unsaid rule are they trying to protect?</p>

<p>Studies have shown that applicants get fearful when over 50% of the class size was filled via ED (paraphrasing Byerly here).</p>

<p>Most ED schools back off a bit when their ED admits creep up on 50%, though they let it creep just as close as they dare; eg, Penn, Princeton and Columbia.</p>

<p>These three schools refuse to report exactly how many ED deferreds they admit later, however, so that it is entirely possible that more than 50% of each entering class at Penn, Princeton and Columbia are original ED applicants and not "ordinary" RD applicants.</p>

<p>Good luck trying to pin them down on this!</p>