Definitely has been plenty of score inflation - you can compare the tables from a while ago - 2001, 2003, etc and currently and the percentiles have shifted even. I won't complain too much but in 2003 my 750 was 99th and right now it is 98th
Test prep is improving significantly but the biggest factor is test takers are taking GMAT more seriously and there is a lot more of them. In 2002 when we just started, there was Princeton, Kaplan
, and Veritas
had a small hut on the beach of Malibu (just kidding). Today there are quite a few more players. GMAT is becoming more of an asset than just a pass/fail mark, though I would argue somewhat that top 20 still consider GMAT as a pass/fail - other's don't and will award scholarships based on scores.
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