When we plot the relationship between demographic data (e.g., growth rate of the workingage population) and the output gap, we usually do not see a strong direct correlation. This may reflect the fact that the impact on the output gap may be felt indirectly through various complex channels.
See ECB (2021), “ECB to invest in Bank for International Settlements’ green bond fund”, 25 January. 6 Recently, the ECB and the national central banks defined a common Eurosystem framework for applying  sustainable and responsible investment principles in the euro-denominated non-monetary policy portfolios that they manage themselves.