Primary school is free but not compulsory and lasts for six years. Secondary schooling is in two stages of three plus three years. In 1996 primary schools had an enrollment of 124,513 students and 4,118 teachers, while secondary schools had 32,097 students and 1,547 teachers. The pupil-teacher ratio at the primary level was 33 to 1 in 1999. In the same year, 70% of primary-school-age children were enrolled in school, while 23% of those eligible attended secondary school. There were nine higher-level schools, including a teachers' training college. Projected adult literacy rates for the year 2000 stand at 63.5% (males, 56.2%; females, 70.4%). Educational expenditure accounted for 21.2% of total government expenditure in 1996. As of 1999, public expenditure on education was estimated at 4.8% of GDP.