The forecasted air pollution-related energy tax revenue in Italy, expressed as a percentage of GDP, remains relatively stable from 2024 to 2028, fluctuating between 2.21% and 2.2%. This steadiness suggests minimal year-on-year variation during this period. The lack of significant change in revenue proportion indicates a stable enforcement of energy taxes relative to economic output.

Future trends to watch for include:

Potential policy shifts aimed at reducing air pollution which may adjust tax structures or rates.
Economic growth or contraction effects on tax revenue's GDP proportion.
Technological advancements in energy efficiency impacting tax revenue calculations.