The Institute for Security Studies (ISS) in Pretoria published in March 2015 a study titled "Power and Influence in Africa: Algeria, Egypt, Ethiopia, Nigeria and South Africa" by Jakkie Cilliers, Julia Schunemann, and Jonathan D. Moyer, all of ISS.
The authors looked at Africa's "big five" over the next 25 years: Algeria, Egypt, Ethiopia, Nigeria, and South Africa on the basis that they potentially hold the greatest amount of power in Africa. Collectively, they represent 60 percent of the African economy, 40 percent of Africa's population, and 58 percent of the the continent's military spending. By 2040, Africa's total relative power is forecast to surpass that of the declining European Union and the United States. At the same time, Africa will likely remain at the margins of global power because it does not speak with one voice or act in unison. Nigeria and Ethiopia are expected to grow considerably in the next 25 years while Egypt, South Africa, and Algeria are forecast to remain stagnant or experience a slight decline.
ISS published on 25 March 2015 a summary of the report titled "Africa and Global Power: On the Rise, but at the Margins."