The graph demonstrates how the population of wild gorillas changed from 1990 to 2015.
The most striking feature is that Ungada had the most gorillas throughout the whole period, although its numbers decreased significantly from considerably more than 7,500 in 1990 to exactly 7,500 in 2015. Likewise, in the Central African Republic, despite the drop, the population remained around 5,000 in both years. The numbers declined noticeably in Rwanda from 2,5000 to just above 0. However, the four other contries ( Gabon, Nigeria, Cameroon and Angola) witnessed a marginal increase. Nigeria’s gorillas maintained almost double the three other countries with populations slightly over 2,500 in both years.
Overall, the numbers of wild gorillas decreased over the period. In most contries they have never reached 2,500 with the exception of Uganda, Central African Republic, where there were marked falls but the numbers remained noticeably more than the other countries, and Nigeria.