By 1980 the percentage of students enrolled in primary schools were high, but the schools reported high dropout rates and regional enrollment gaps (most enrollees were concentrated in the cities). Only one in four counties had universal primary education. On average, 10 percent of the students dropped out between each grade. During the 1979–83 period, the government acknowledged the "9-6-3" rule, that is, that nine of ten children began primary school, six completed it, and three graduated with good performance. This meant that only about 60 percent of primary students actually completed their five-year program of study and graduated, and only about 30 percent were regarded as having primary-level competence. Statistics in the mid-1980s showed that more rural girls than boys dropped out of school.