Having made official the ranking methodology, it disclosed that it is based on 10 different indicators that measure universities' academic performance and reputations.[1] The ranking has since been revised and expanded to cover 1,500 institutions in 81 countries and now includes five regional and 28 subject rankings.[2] Employing 13 indicators and based largely on data provided by Clarivate, the U.S. News global ranking is methodologically different from its ranking of American institutions; global universities are rated using factors such as research reputation, academic publications, and the number of highly cited papers.[3][4]