The figure is the result of a series of inquiries conducted by independent institutions, including the Economist's Intelligence Unit, the Merchant International Group, Freedom House, the World Economic Forum and the World Market Research Centre.
Taj rezultat posledica je serije istraživanja nezavisnih ustanova, među kojima su časopis Ekonomist (the Economist), Merčant Internešnel Grup (Merchant International Group), Fridom Haus (Freedom House), Svetski ekonomski forum (the World Economic Forum) i Centar za istraživanje svetskog tržišta (World Market Research Centre).