Before revision: The member countries of the IBI at the time when it had the most members were the following: Algeria, Argentina, Benin, Bolivia, Brazil, Burkina Faso (formerly the Republic of Upper Volta), Cameroon, Colombia, Congo, Costa Rica, Cuba, Chile, Ecuador, Egypt, France, Gabon, Ghana, Guinea, Haiti, Iraq, Italy, Ivory Coast, Jordan, Lebanon, Liberia, Madagascar, Mali, Morocco, Mexico, Nicaragua, Niger, Nigeria, Panama, Sao Tomé and Principe , Senegal, Spain, Syria, Swaziland, Togo, Tunisia, United Arab Emirates, Venezuela, Zaire.
After revision: The member countries of the IBI at the time when it had the most members were the following: Algeria, Argentina, Benin, Bolivia, Brazil, Burkina Faso (formerly the Republic of Upper Volta), Cameroon, Colombia, Congo, Costa Rica, Cuba, Chile, Ecuador, Egypt, France, Gabon, Ghana, Guinea, Haiti, Iraq, Italy, Ivory Coast, Jordan, Lebanon, Liberia, Madagascar, Mali, Morocco, Mexico, Nicaragua, Niger, Nigeria, Panama, São Tomé and Príncipe , Senegal, Spain, Syria, Swaziland, Togo, Tunisia, United Arab Emirates, Venezuela, Zaire.