Summer Olympic Games demand for tickets to all levels of each event, there was controversy when seats set aside for sponsors and National Delegations went unused in the early days. A system of reallocation was put in place so the empty seats were filled throughout the Games. Rio de Janeiro, Brazil hosted the 2016 Summer Olympics, becoming the third city in the Southern Hemisphere to host the Olympic Games after Melbourne, Australia, in 1956 and Sydney, Australia, in 2000, and the first South American city to host the Olympics. The preparation for these Games was overshadowed by controversies, including the instability of Brazil's
Comoros at the 2000 Summer Olympics International Olympic Committee on 1 January 1993. Comoros joined Olympic competition at the 1996 Summer Olympics and have participated at every Summer Olympic Games since, though the nation has yet to debut at the Winter Olympic Games. Sydney was the second appearance by the nation in a Summer Olympiad. The 2000 Summer Olympics were held from 15 September to 1 October 2000; a total of 10,651 athletes represented 199 NOCs. The Comoros delegation to Sydney consisted of two track and field athletes: Hadhari Djaffar and Sandjema Batouli. Sandjema Batouli was 18 years old at the time of the Sydney Olympics