Social sustainability is considered as the least defined and addressed pillar among the three pillars of sustainability. Social sustainability goals and targets within sustainable development goals are currently considered vital factors for human beings. Therefore, countries continuously evaluate their performance with respect to achieving social sustainability goals to promote required commitments and partnerships to address existing social problems and to maximize social satisfaction of their citizens. In this regard, this paper evaluates the social sustainability performance in seven developed countries that are included in the Group of Seven (G7) as one of the most important intergovernmental economic organizations. Assessing the performance of the countries is conducted based on real data from Organisation for Economic Co-operation and Development (OECD) dataset, where fourteen indicators are selected from different aspects that have noticeable roles on social sustainability. Evaluation of countries is done through a novel integrated data-driven weighting system based on CRITIC and Shannon's Entropy methods, and CoCoSo method. Using the integrated data-driven weighting system, the weight of indicators is determined by using an aggregation operator to combine weights obtained from CRITIC and Shannon's Entropy. The proposed integrated data-driven weighting system is designed to remove the biasedness and subjectivity of experts' opinions that can happen using other weighting methods. Then, countries are comparatively evaluated and ranked using the CoCoSo. Based on the results of the proposed model, France shows the best performance with respect to social sustainability indicators.