The amount of Domestic material consumption (DMC) that measures the total amount of fossil fuels used by an economy. It is defined as the annual quantity of fossil fuels extracted from the domestic territory, plus all physical imports and minus all physical exports. It includes intermediate and final consumption until released to the environment. Fossil fuel is a generic term for non-renewable natural energy sources such as coal, natural gas and oil that were formed from plants and animals (biomass) that existed in the geological past (for example, hundreds or millions of years ago). Fossil fuels are carbon-based and currently supply most human energy requirements.