This report attempts to resolve disagreements about trends in minority enrollments in postsecondary education institutions and to examine various factors that might help explain the enrollment trends. Among the study's findings were the following: (1) in the total group of individuals, aged 18-24, the overall enrollment rate of blacks has changed little since the mid-1970s; (2) the proportion of black high school graduates, aged 18-24, that is enrolled in college has declined substantially from a peak of nearly 33 percent in the mid-1970s; and (3) the enrollment rate of Hispanic youth has been stable since the late 1970s, though it remains lower than during the peak years of the mid-1970s. Possible factors causing the enrollment trends, such as military enlistments and family income differences, are analyzed. Data sources (the Current Population Survey and the Integrated Postsecondary Education Data System) are described in an appendix. Includes 51 references. (JDD)