The Union-wide quantity of allowances issued under this Chapter each year from 2027 shall decrease in a linear manner beginning in 2024. The 2024 value shall be defined as the 2024 emission limits, calculated on the basis of the reference emissions under Article 4(2) of Regulation (EU) 2018/842 of the European Parliament and of the Council (
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) for the sectors covered by this Chapter and applying the linear reduction trajectory for all emissions within the scope of that Regulation. The quantity shall decrease each year after 2024 by a linear reduction factor of 5,10 %. By 1 January 2025, the Commission shall publish the Union-wide quantity of allowances for the year 2027.