My University publishes GPAs for academic honors based on the college. It is the average GPAs for the past five years and they use it as a basis for graduation. Perhaps those numbers would better reflect the differences in GPAs for someone who is a Family and Consumer Sciences major, than to the sister who is an Electrical Engineering major. This only covers the top 3, 6 and 10 percent of students, but you could extrapolate downwards from there.
http://www.registrar.uidaho.edu/grad...ic-honors.html