Article 4
1. All assigned amount units issued for the second commitment period available in the Union registry after the Union has complied with its obligation laid down in Article 11(3) of Regulation (EU) No 525/2013 and after any transfer of assigned amount units pursuant to implementing acts adopted on the basis of Article 10(7) of Regulation (EU) No 525/2013 has been carried out (‘Union surplus’) shall be returned to the Member States at the end of the second commitment period. 2. The Union surplus shall be allocated to the Member States as follows: (a) one sixth of the Union surplus to Member States that reduced their total average annual emissions by more than 20 % relative to their individual base year or period under the Kyoto Protocol by the end of the second commitment period proportionally to their overachievement in tonnes; (b) one third of the Union surplus to Member States that receive a transfer under point (a) and that have a GDP per capita (GDP in 2013 in euro at market prices) below 60 % of the Union average proportionally to their overachievement in tonnes; (c) one third of the Union surplus to all Member States proportionally to their total emission levels as set out in Table 1 in Annex I to this Decision; (d) one sixth of the Union surplus to Member States that have a GDP per capita (GDP in 2013 in euro at market prices) below 90 % of the Union average proportionally to their total emission levels as set out in Table 1 in Annex I to this Decision.