• Data reference period
• Geographic localization (Portugal)

• ECONOMIC TERRITORY:  Territory that consists on: (a) the geographic territory administered by a government within which persons, goods, services and capital move freely; (b) any free zones, including bonded warehouses and factories under customs control; (c) the national air-space, territorial waters and the continental shelf lying in international waters, over which the country enjoys exclusive rights; (d) territorial enclaves (i.e. geographic territories situated in the rest of the world and used, under international treaties or agreements between States, by general government agencies of the country (embassies, consulates, military bases, scientific bases, etc.); (e) deposits of oil, natural gas, etc., in international waters outside the continental shelf of the country, worked by units resident in the territory as defined in the preceding subparagraphs.
• AIR EMISSIONS (ANTHROPOGENIC):  Result in the introduction into the atmosphere, by human activity, of chemicals, particulate matter, or biological materials that cause harm or discomfort to living beings, or damages the environment.
• REFERENCE PERIOD:  Period to which the information refers and which may be a specific day or a time interval (month, fiscal year, calendar year, among others).

CO₂ emissions/ Value added by the manufacturing industry