[BostonCard]

I think your calculations are more or less correct.  I found the national center for education statistics data for Stanford here:
https://nces.ed.gov/collegenavigator/?q=...44#outcome

Undergraduate transfer-in enrollment was 46 in 2022.
The retention rate (ie, "the percentage of first-time students who are seeking bachelor's degrees who return to the institution to continue their studies the following fall.for first-time students", presumably excluding those who received a degree) is 98%, so with a total non-graduating undergraduate enrollment of about 6000, ~120 or so don't come back the subsequent year.
The overall graduation rate was 95% for those who started in 2016.  The transfer out rate is listed as 0% (I assumed rounded down from <0.049%), though down below, it notes that of the full-time, first-time degree-seeking students who entered in 2014/15, 97% received their bachelor's degree, and 1% enrolled in a different institution.  That comes out to 20, maybe 30 if you round down, students who transferred out.  Any way you count it, there were not a lot of transfers.

BC

[BostonCard]

I think your calculations are more or less correct.  I found the national center for education statistics data for Stanford here:
https://nces.ed.gov/collegenavigator/?q=...44#outcome

Undergraduate transfer-in enrollment was 46 in 2022.
The retention rate (ie, "the percentage of first-time students who are seeking bachelor's degrees who return to the institution to continue their studies the following fall.for first-time students", presumably excluding those who received a degree) is 98%, so with a total non-graduating undergraduate enrollment of about 6000, ~120 or so don't come back the subsequent year.
The overall graduation rate was 95% for those who started in 2016.  The transfer out rate is listed as 0% (I assumed rounded down from <0.049%), though down below, it notes that of the full-time, first-time degree-seeking students who entered in 2014/15, 97% received their bachelor's degree, and 1% enrolled in a different institution.  That comes out to 20, maybe 30 if you round down, students who transferred out.  Any way you count it, there were not a lot of transfers.

BC