Here's my understanding of it:
First Box -->
Columns: Science/Non-science/Total
Rows: Freshman/Sophomore/.../Total/Post-Baccalaureate/Cum. Undergrad/
Graduate/Overall
Second Box -->
GPA by course type (Biology/zoology, Inorg. Chem, Org. Chem, Biochem, Physics, Other Sci., Math, English, Beh. Sci., Other Non-Sci., Total)
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Any undergraduate class you take after you receive your bachelor's degree is counted in post-baccalaureate GPA, averaged into the Cum. Undergrad, and in the Overall GPA's. If you retake a class, the most current retake replaces the old class (you ignore the old class in GPA calculations).