Estimating salary regressions on data from the 1993-94 Baccalaureate and Beyond Longitudinal Study showed that gender differences in total college credits accounted for more of the male-female salary gap than majors, grades, or institutions. Gender differences in job sector, industry, and hours worked had the largest effect on the gap. However, as much as 75% remains unexplained by academic or labor market variables. (Contains 33 references.) (SK)