The third category, economically backward (rural) areas (around 25 percent of China's population ) were to popularize basic education without a timetable and at various levels according to local economic development, though the state would try to support educational development. The state also would assist education in minority nationality areas. In the past, rural areas, which lacked a standardized and universal primary education system, had produced generations of illiterates; only 60 percent of their primary school graduates had met established standards.