For the 2012 report, a new "Pilot Trend EPI" was developed to rank countries based on the environmental performance changes occurred during the last decade, allowing to establish which countries are improving and which are declining.
就2012年报告来说，新“趋势实验指数”被用于评估在国家过去数十年间对环境改善的努力，研究哪些国家在进步，哪些在退步。