I was told by an AO (pre-COVID) that they also take into account where the applicant went to school.
A 65 percentile in math is a red flag if the applicant goes to a well known K-8 private school where SSAT prep is part of the curriculum.
A 65 percentile in math is not a red flag if the applicant is from a low performing public school district and the applicant is acing the highest level math class their school offers.