The is the guide to kanji characters and their readings, announced officially by the Japanese Ministry of Education. Current jōyō kanji are those on a list of 2,136 characters issued in 2010. It is a slightly modified version of the tōyō kanji, which was the initial list of secondary school-level kanji standardized after World War II. The list is not a comprehensive list of all characters and readings in regular use; rather, it is intended as a literacy baseline for those who have completed compulsory education, as well as a list of permitted characters and readings for use in official government documents. Due to the requirement that official government documents make use of only jōyō kanji and their readings, several rare characters are also included due to their use in the Constitution of Japan, which was being written at the same time the original 1,850-character tōyō kanji list was compiled. The 2,136 kanji in the jōyō kanji consist of: 1,026 kanji taught in primary school (Grade 1-6) (the kyōiku kanji) 1,110 additional kanji taught in secondary school (Grade 7-12) Changes from the tōyō kanji In 1981, the jōyō kanji replaced the tōyō kanji as the standardized list of common kanji. The differences between the two consisted of 95 additional characters, and the simplification of as . The 95 additional characters are as follows: History 1923: The Ministry of Education specified 1,962 kanji and 154 simplified characters. 1931: The former jōyō kanji was revised and 1,858 characters were specified. 1942: 1,134 characters as standard jōyō kanji and 1,320 characters as sub-jōyō kanji were specified. 1946: The 1,850 characters of tōyō kanji were adopted by law "as those most essential for common use and everyday communication". This list included 881 'basic requirement' kanji for elementary school. 1981: The 1,945 characters of jōyō kanji were adopted, replacing the list of tōyō kanji. 2010: The list was revised on 30 November to include an additional 196 characters and remove 5 characters (, , , , and ), for a total of 2,136. The amendment also made changes to the readings of kanji present in the previous jōyō kanji list. Twenty-eight kanji gained new readings, three kanji lost obscure readings and the kun'yomi of was changed from to . The 196 additional characters are: Note: Characters in bold are used in the names of prefectures. Jōyō kanji followed by a character in brackets are not