Coverage and indicator selection criteria The ETI 2025 assesses 118 countries. To be covered in the index, a country needs to have data for most of the index’s 43 indicators, including sufficient coverage for each dimension. The following principles guide the selection of indicators: 1. Relevance: alignment of parameters with core aspects of the energy transition 2. Recency and comparability: use of the most recent and cross-country comparable data 3. Source quality and objectivity: reliance on credible, widely recognized and independent data sources Comparability and updates in the ETI 2025: The ETI is a dynamic benchmark, with structural and indicator-level refinements applied each year to reflect evolving transition priorities and data availability. Moreover, data sources frequently revise data, changing historical results. As a result, direct comparisons of country rank and score between the ETI 2025 and previously published editions should be made with caution.The following updates have been made to the 2025 ETI: 1. Indicator removals The following indicators have been excluded from ETI 2025 due to data limitations, redundancy or methodological changes: –Gas supply resilience –International financial flows –Regulatory Indicators for Sustainable Energy (RISE) Cook Score –Rule of law –Investment in renewable energy 2. Indicator name changes To better reflect the parameters measured, the following indicators have been renamed: –Carbon prices Net-effective carbon rates –Quality of education Labour market competitiveness –Public R&D spend R&D as share of GDP 3. New indicator addition Economic freedom and investment in renewable energy has been introduced as a new indicator under the regulation and political commitment and finance and investment sub- dimensions, respectively, to improve coverage of macroeconomic enablers in the energy transition. Fostering Effective Energy Transition 2025 53