<p>I'm no statistician, but percentile numbers dropping could suggest a couple things;
1) colleges don't care as much about SAT scores as they did before</p>
<p>2) another possible reason; colleges take other factors into consideration more than SATs now (like EC's, essays, recs, and grades), as the applicant pool grows larger (and assumingly, more students with 2400s and near perfect scores apply more, requiring them to narrow it down further than just test scores). </p>
<p>3) Average SAT scores ARE actually dropping, says many news articles (just google average SAT scores dropping, and you'll see numerous articles about it). The most likely reason is due to the new SAT with the extra writing section. Here's an excerpt from one such article:
"Some colleges are reporting double-digit drops in the average SAT scores of applicants this year, even as other credentials, such as class rank and college-prep coursework, remained similar to or grew stronger than last year's.
Among schools reporting large drops: The nine-campus University of California system, which saw a 15-point drop on average among applicants, Average composite scores for the ACT, a rival college entrance exam, were unchanged from last year.</p>
<p>It's not yet clear what the drops mean, but colleges are particularly curious because the scores are almost completely based on the new SAT, introduced last year by the non-profit College Board, which owns the test."</p>
<p>Some Reasons for why average SAT scores have dropped:
-new test is longer, fatigue; 3hrs 45 minutes instead of 3 hrs.
-new test includes writing section
-people retake test less (due to increase in costs/time) (retaking test improves score 30 points on average)</p>
<p>Another article says: "The drop in average SAT scores is a statistical fluke. Thirty years ago, advantaged and over-achieving white students formed a disproportionate share of all those taking the test. Today, a growing share of minority and lower class whites are taking the test also, and they tend to score lower than advantaged whites. However, the scores of minorities have been rising over the last few decades, even faster than whites. Thus, everyone's scores are generally rising, even though the average is dropping." </p>
<p>Hope this helps!</p>