Education is compulsory from ages 7 to 15 and both primary and secondary education are free. However, only 71 percent of children of the relevant ages were enrolled in primary school in 1996, and only 64 percent in secondary school. The overall literacy rate is 93 percent, but the rate is higher for males (98 percent) than it is for females (89 percent). Literacy rates are not uniform among ethnic groups. Albanian girls receive less schooling than girls of other groups, and Albanians in general have lower literacy rates. Schooling has been particularly difficult for ethnic Albanians since 1990.