For the most part, you are correct, but it depends on the HS. Many HS’s will provide a school profile which may list GPA’s by decile or some other type of scattergram. [url=http://www.newton.k12.ma.us/cms/lib8/ma01907692/centricity/domain/28/counseling/nnhsprofile2014-2015.pdf]Here[/url] is an example. Additionally, if numerous applicant from the same school apply, one should assume that the AO will sort in GPA order even if the school does not rank.