This graph shows an increase of years of schooling that child are expected. It's basically means a period of compulsory education. As you can see in table, expected years of schooling per child in china are increasing per each 5 years. The compulsory education law which established 9 - year compulsory education was established in 1986 and was enforced. In implementing the policy, taking into consideration the economic and cultural conditions of each region, a policy of gradual implementation by region is taken. By 2005, 9-year compulsory education is being implemented in about 95% of the country. As you can see in table, they are keeping a line of 9 years in 1990-2000. In 2003, china established a Higher education. This system adds 3 year on compulsory education of china. From 2011, china keeping a line of 12.9 years till today.