In the South African schooling system, grades 1 through 7 constitute primary schooling (ISCED level 1), grades 8 and 9 constitute lower secondary (ISCED level 2), grades 10 to 12 constitute upper secondary (ISCED level 3) with a national school-leaving examination at the end of grade 12. Then, with regard to the post-schooling levels, a diploma or certificate without complete schooling would be at ISCED level 4 (post-secondary, non-tertiary) and diploma with grade 12 or degree would be at ISCED level 5 and, in a few cases, ISCED level 6. Once again we have substantial changes in the distribution of the population of household heads.