Base year emissions, under the Kyoto Protocol, are defined as the aggregate anthropogenic carbon dioxide equivalent emissions of the GHGs listed in Annex A sources in a historical base year. For most Annex I Parties, the historical base year is 1990 but Parties included in Annex I undergoing the process of transition to a market economy may choose a year or period other than 1990, in accordance with Article 3, paragraph 5. Annex I Parties may choose to use 1995 as the base year for total emissions of hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulphur hexafluoride (SF₆), in accordance with Article 3, paragraph 8 and 1995 or 2000 as its base year for nitrogen trifluoride (NF₃) in accordance with Article 3, paragraph 8 bis of Doha Amendment to the Kyoto Protocol.

If the land use, land-use change and forestry sector constituted a net source of greenhouse gas emissions in the base year or period, then net emissions from the part relating to the conversion of forests (deforestation) will be included in the total national emissions for that year or period.

The table below provides, for Annex I Parties included in Annex B to the Kyoto Protocol:

1. Quantified emission limitation or reduction commitment inscribed in the third column of Annex B in the Doha Amendment to the Kyoto Protocol or in accordance with Article 4 of the Kyoto Protocol (expressed as percentage of base year or period level);
2. Base year for CO₂, CH₄ and N₂O;
3. Selection of the base year for HFCs, PFCs, SF₆ and NF₃;
4. Base year level of total national emissions as determined by the initial review for the second commitment period, expressed in tonnes CO₂ equivalent;
5. Source of information on the base year and base year emissions level.

* A Party undergoing the process of transition to a market economy (an EIT Party).
1. Belarus has not submitted the Initial Report as of 18 November 2017.