President Falk is not as transparent as former President Schapiro was about admissions statistics, but he does, on occasion, provide some interesting details. Mary Dettloff kindly provided this background on a Falk speech from several years ago.
In 2013, the number of applicants with an AR2 rating was 1,269. I am confirming that number for you since Adam did mention it at a private, not public, event that you attended. The information for the Class of 2021, however, is not information we have to report publicly anywhere, so I will not be providing that information.
Fair enough! And thanks, as always, to Mary for all her help with our endless questions.
1) “AR2” — which is the insider abbreviation for “Academic Rating 2” — is a standard designation in the ranking system that the Admissions Department uses. A reminder:
- Academic 1: at top or close to top of HS class / A record / exceptional academic program / 1520 – 1600 composite SAT I score;
- Academic 2: top 5% of HS class / mostly A record / extremely demanding academic program / 1450 – 1520 composite SAT I score;
- Academic 3: top 10% of HS class / many A grades / very demanding academic program / 1390 – 1450 composite SAT I score;
- Academic 4: top 15% of HS class / A – B record / very demanding academic program / 1310 – 1400 composite SAT I score;
2) We know from the 2005 Alumni Review article that any applicant without a “hook”  is rejected if their Academic Rating is below a 2 — that is why the raw number of AR2s is so important. Williams could fill its entire class with AR1s and AR2s! 
3) Recall the details from the latest Common Data Set (pdf):
It is a coincidence (?) that the 1450 combined math/verbal SAT average marks the cut off for AR2. But it sure is convenient! Speaking very broadly, half of every Williams class is admitted based on their academic ambition/talent/conscientiousness. The other half would not have been admitted were it not for their race/income/athleticism.
4) If it were me, I would place a lot more emphasis on academics and a lot less on everything else. What would Williams look like if we only admitted AR2s and above? Assume that we still cared about race/income/athletics. That is, we still give preference to AR2 hockey players over AR1 non-hockey players. What would our racial numbers look like? How well would our sports teams do?
 Almost all hooks are involve race/income/athletics. There are 66 athletic “tips” who would not have been admitted were it not for a nod from a Williams coach, and another 30 or so “protects” whose chances of admissions were only 50/50. Williams, like all elite schools, has huge problems finding enough qualified black/Hispanic applicants, and so is happy to take plenty who are AR3 or 4. Williams, especially via Questbridge, seeks applicants from poor families. (And the Development Office creates spots for (how many?) children of big donors.)
 Of course, it is hard to know for certain that this is true. We would need to know two other pieces of information: How many AR1 applicants are there and how well Williams yields among AR1s and 2s? Contrary opinions are welcome, but my strong sense is that, with so many AR2s (hundreds of whom Williams rejects outright), Williams could easily fill a class in which every student scored above 1450 in math/verbal SAT (with high school grades to match).