Although the formula for the USNA "whole candidate score" is a well-kept secret, academics are supposed to be more than half of the total. That includes GPA/class rank and SAT/ACT scores. Usually a candidate needs a score of ~600 on each section of the SAT to even get a candidate number. Look through the USNA web site. Each year they post information about the class profile of the incoming Plebes. That profile shows overall grades/class ranks, test score ranges, ECAs, and so forth.