Best to use the primary source for number of athletes. Tulane had 318 unduplicated athletes in 17/18 school year (most recent data). https://ope.ed.gov/athletics/#/institution/details
Total 17/18 ug enrollment was 6,571 per the CDS, so 4.8% athletes…and not all of those 318 athletes are recruited, or receive athletic scholarships…so we can’t assume all those athletes are in the bottom quartile of stats.
Lastly, it is not clear how Tulane calculates average GPA in the CDS, specifically whether they use all courses off the transcripts or only courses from the five core areas…those two ways to calculate an average GPA can lead to very different results.