The 2014 EPI takes into account whether an issue is material, that is relevant, for each country. For example, a country that lacks a coastline does not receive a score for Fisheries. The goal of materiality is to level the playing field between countries so that they can be more consistently compared to one another. Because countries have different natural resources, topographies, and geographies, the EPI tries to take these considerations into account.
This spreadsheet details the materiality filters used as well as the population, land area and income group of each country.