Like other major variables in the PTC, the flags for whether or not a student has declared a major that is considered STEM is measured at the semester level going out twenty-one semesters and for up to three majors in a single semester. The flags are of the general form
Where the first asterisk indicates which of three majors this is and the second and third asterisks indicate which semester is being measured. Thus STEM1_CODE_SEM01 measures a student’s first major in their first semester while STEM3_CODE_SEM08 measures their third major in their eighth semester. Note that there are both _CODE_ and _DESC_ versions of each variable. The following is the breakdown of code and description:

The full list of all 126 variables is not being included here for space reasons.